Microwave normal-pressure plasma jet array based on power divider

Abstract

The invention discloses a microwave normal-pressure plasma jet array based on a power divider, and relates to the field of microwave normal-pressure plasmas, the microwave normal-pressure plasma jet array comprises an outer cavity and an upper cavity arranged at the upper end of the outer cavity, a metal cover plate is arranged at the upper end of the upper cavity, and an inner conductor is arranged in the outer cavity. According to the microwave normal-pressure plasma jet array based on the power divider, microwave low-temperature plasmas can increase the excitation, ionization and dissociation processes of gas molecules, the number of excited sub-state atoms is large, the ionization and dissociation degrees of the plasma to gas are one order of magnitude higher than those of other types of plasmas (such as radio-frequency electric field plasmas), the plasma density is large, and the plasma density is high. The plasma beam is high in ionization degree, large in energy and high in activity, and related physical and chemical reactions are easier to occur or initiate, so that the plasma beam is higher in efficiency in medical treatment depending on plasma active components, the bacteria can be killed by hitting a culture dish containing the bacteria or a skin wound, and the sterilization effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of microwave atmospheric pressure plasma, in particular to a microwave atmospheric pressure plasma jet array based on a power divider. Background Art

[0002] In recent years, the research on microwave atmospheric pressure plasma has become increasingly popular and has very considerable application value. It has been applied in biomedicine, material processing, agricultural production, pollution reduction and other fields.

[0003] In the prior art, the treatment area of ​​a single jet unit under normal pressure is generally small, which cannot meet the user's requirements for efficient, rapid and large-area treatment in practical applications.

[0004] In order to overcome the above-mentioned shortcomings, a Chinese patent of the prior art (publication number CN112996209B) discloses a structure and an array structure of a microwave-excited atmospheric-pressure plasma jet, aiming to provide a structure for exciting plasma without electrodes, with low manufacturing cost and easy processing, so as to avoid secondary pollution to the excited plasma, comprising: a coaxial joint, an excitation structure comprising: a feeding transmission line structure, a first metal layer, a dielectric substrate layer and a second metal layer; the first metal layer is connected to the inner conductor of the coaxial joint through the feeding transmission line structure, and the second metal layer is connected to the outer conductor of the coaxial joint; a plurality of metal vias are arranged along the length direction of the substrate to connect the first metal layer and the second metal layer, the metal vias enclose a dielectric substrate layer area, and a quartz tube is inserted into the through hole opened on the substrate; the first and second metal rings outside the quartz tube are respectively connected to the first and second metal layers; the coaxial joint transmits the microwave signal to the dielectric substrate layer, and the metal vias confine the microwave signal to the dielectric substrate layer area to excite the gas in the quartz tube into plasma.

[0005] In order to overcome the above-mentioned shortcomings, a Chinese patent of the prior art (publication number CN119155875A) discloses a normal-pressure microwave plasma jet device, comprising an outer conductor, an inner conductor coaxially arranged inside the outer conductor, a nozzle threadedly connected to the bottom end of the outer conductor, a pin at the end of a radio frequency connector connected to the inner conductor through a connecting conductor, an air pipe joint threadedly connected to the outer conductor, a short-circuit screw plug threadedly connected to the top end of the outer conductor, a short-circuit reflective surface provided at the bottom of the connecting piece installed therein, a gas guide ring nested on the inner conductor and located between the radio frequency connector and the air pipe joint; a stable normal-pressure microwave plasma jet can be obtained without configuring a complex control module to adjust the impedance matching degree of the system, the gas flow state can be made more stable, and the plasma at the outlet can be avoided from being affected, and the short-circuit reflective surface is also designed to be threadably adjusted up and down, and the impedance matching effect can be achieved by fine-tuning the short-circuit reflective surface.

[0006] Although the existing technology can overcome the above-mentioned shortcomings, there are still other problems in its operation, such as: the area of ​​microwave atmospheric pressure plasma discharge is small, which is not conducive to user use. At the same time, during discharge, due to external factors, it is easy to cause uneven discharge, and in terms of energy utilization, the energy utilization rate is not high. Summary of the invention

[0007] The purpose of the present invention is to provide a microwave atmospheric pressure plasma jet array based on a power divider to solve the problems mentioned in the above background technology that the microwave atmospheric pressure plasma discharge area is small, which is not conducive to user use, and at the same time, when discharging, it is easy to cause uneven discharge due to external factors, and in terms of energy utilization, the energy utilization rate is not high.

[0008] To achieve the above object, the present invention provides the following technical solution: a microwave atmospheric pressure plasma jet array based on a power divider, comprising an outer cavity and an upper cavity arranged at the upper end of the outer cavity, and a metal cover plate is arranged at the upper end of the upper cavity;

[0009] An inner conductor is arranged inside the outer cavity, and a surface of the inner conductor is arranged between the outer cavity and the upper cavity, and a gap is arranged between the outer cavity and the inner conductor, and a radio frequency connector is arranged outside the inner conductor, and the radio frequency connector is arranged in an "N" type;

[0010] The upper end of the radio frequency connector is provided with a coaxial body through a mounting head, and a microwave atmospheric pressure plasma jet unit is provided inside the coaxial body, and the microwave atmospheric pressure plasma jet unit is provided with a conductor column, and the conductor column is embedded in the coaxial body.

[0011] Furthermore, a microwave source is provided at the lower end of the outer cavity, and the upper end of the microwave source is connected to the inner conductor, and the outer side of the inner conductor is fixedly mounted on the inner side of the outer cavity and the upper cavity through a supporting medium.

[0012] Furthermore, the inner conductor is in the shape of a stepped impedance transformation structure with different diameters, an isolation dielectric plate is disposed inside the upper cavity, and a conductor probe of the isolation dielectric plate is embedded inside the inner conductor.

[0013] Furthermore, the lower end of the coaxial body is connected to the mounting head via the coaxial connecting end, and air guide holes are provided on the left and right sides of the coaxial body, and working fluid is arranged inside the air guide holes, and the lower end of the working fluid is connected to the gas cylinder.

[0014] Furthermore, a perforated Teflon layer is provided inside the upper end of the coaxial body, and a top rotating cover is threadedly installed on the upper end of the coaxial body.

[0015] Furthermore, a discharge tip is disposed at the upper end of the conductor column, a dielectric layer is disposed at the upper end of the discharge tip, the middle end of the conductor column penetrates the inside of the perforated Teflon layer, and the lower end of the conductor column is connected to the upper end of the mounting head.

[0016] Furthermore, a servo motor is fixedly mounted on the upper end of the metal cover plate, a first bevel gear is fixedly mounted on the output end of the servo motor, a second bevel gear is meshedly mounted on the lower end of the first bevel gear, and a threaded screw is fixedly mounted on the outer side of the second bevel gear.

[0017] Furthermore, the left and right ends of the threaded screw are rotatably mounted on the upper end of the metal cover plate through a horizontal plate, a movable shift block is threadedly mounted on the surface of the threaded screw, and a limiting guide rod is installed through the front and rear ends of the movable shift block, and the left and right ends of the limiting guide rod are fixedly mounted on the inner side of the horizontal plate.

[0018] Furthermore, a column plate is fixedly installed on the upper end of the metal cover plate, and a rotating rod is rotatably installed on the upper end of the column plate, and a contact plate is fixedly installed on the middle end of the rotating rod, and a sealing adjustment block is provided inside the contact plate, and the lower end of the sealing adjustment block is rotatably installed on the upper end of the movable shift block.

[0019] Furthermore, a groove positioning plate is fixedly installed on the inner side of the coaxial body, and a knocking bump plate is slidably connected to the inner side of the groove positioning plate, and a vibration spring is arranged between the front and rear ends of the knocking bump plate and the inner side of the coaxial body, and the inner side of the knocking bump plate corresponds to the contact plate.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Microwave low-temperature plasma can increase the excitation, ionization, and dissociation processes of gas molecules. There are more excited substate atoms, and the degree of ionization and dissociation of gas is one order of magnitude higher than other types of plasma (such as radio frequency electric field plasma). The plasma has a high density, high ionization degree, high energy, and strong activity. It is easier to cause or trigger related physical and chemical reactions. Therefore, it is more efficient in medical treatment that relies on plasma active ingredients. The plasma beam can be applied to a culture dish containing bacteria or a skin wound to kill the bacteria and achieve a sterilization effect.

[0022] 2. The structure of the device is compact, small, easy to carry, easy to assemble and mass produce. The design of the power divider and the isolation structure therein ensures that the properties of each plasma jet are consistent. The discharge tip of the conductor in the jet unit is detachable, and a suitable discharge tip can be replaced according to the frequency of the microwave source; an open-pored Teflon layer is arranged near the upper end between the conductor column and the coaxial body to assist in constraining the airflow, stabilize the flow of the airflow to a certain extent, and make the airflow at the tip more stable, so that the plasma beam can be stably output, and the plasma jet is hit on the plate to be processed, or at a certain distance from the plate. The plasma cleans the surface of the plate through physical and chemical effects, achieving a better adhesive effect and facilitating bonding.

[0023] 3. When the device is working, the servo motor is started, and the first bevel gear and the second bevel gear at the output end thereof are meshed. With the start of the servo motor, the second bevel gear drives the threaded screw to rotate. When the threaded screw rotates on the inner side of the horizontal plate, it can drive the movable shifting block connected by the thread on its surface. Under the limit of the limit guide rod, the movable shifting block can drive the movable shifting block to move left and right with the rotation of the threaded screw. When the movable shifting block moves, it drives the sealing adjustment block rotating at the upper end. The sealing adjustment block drags the contact plate on the outside. Under the setting of the rotating rod, the contact plate can rotate along the column plate. Therefore, with the movement of the movable shifting block, under the activity of the sealing adjustment block, the upper end of the contact plate is driven to contact the knocking convex plate. After being squeezed by the contact plate, the knocking convex plate knocks the coaxial body along the groove positioning plate. Under the setting of the vibration spring, the knocking effect can be improved, the vibration efficiency can be guaranteed, and the anti-blocking effect can be achieved. When the output frequency inside the coaxial body is avoided, the internal is blocked by impurities, the use efficiency of the device is guaranteed, and the device cannot be used due to impurities. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention;

[0025] Figure 2 It is a bottom view structural schematic diagram of the present invention;

[0026] Figure 3 This is a schematic diagram of the three-dimensional structure of the upper cavity of the present invention when viewed from above;

[0027] Figure 4 It is a schematic diagram of the three-dimensional structure of the present invention in front view;

[0028] Figure 5 It is a schematic diagram of the three-dimensional structure of the outer cavity and the upper cavity being separated according to the present invention;

[0029] Figure 6 It is a schematic diagram of the three-dimensional structure of the coaxial main body of the present invention;

[0030] Figure 7 It is a schematic diagram of the three-dimensional structure of the coaxial main body of the present invention in side section;

[0031] Figure 8 It is a schematic diagram of the three-dimensional structure of the servo motor of the present invention;

[0032] Fig. 9 For the present invention Figure 8 The enlarged structural diagram at A in the middle;

[0033] Fig.10 This is a schematic diagram of the three-dimensional structure of the threaded screw rod of the present invention when viewed from above;

[0034] Fig.11 It is a schematic diagram of the three-dimensional structure of the groove positioning plate of the present invention.

[0035] In the figure: 1. outer cavity; 2. upper cavity; 3. metal cover plate; 4. microwave source; 5. inner conductor; 6. supporting medium; 7. RF connector; 8. isolation medium plate; 9. mounting head; 10. coaxial body; 11. air guide hole; 12. working medium; 13. top rotating cover; 14. perforated Teflon layer; 15. conductor column; 16. discharge tip; 17. dielectric layer; 18. servo motor; 19. first bevel gear; 20. second bevel gear; 21. threaded screw; 22. horizontal plate; 23. limit guide rod; 24. column plate; 25. movable shift block; 26. sealing adjustment block; 27. rotating rod; 28. contact plate; 29. ​​groove positioning plate; 30. knocking bump plate; 31. vibration spring. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Embodiment 1: Figure 1-Figure 5The technical solution shown is a microwave atmospheric pressure plasma jet array based on a power divider. In order to solve the problem that the area of ​​microwave atmospheric pressure plasma discharge is small, which is not conducive to user use, and at the same time, when discharging, it is easy to cause uneven discharge due to external factors, and in terms of energy utilization, the energy utilization rate is not high, the following technical solution is disclosed: an outer cavity 1 and an upper cavity 2 arranged at the upper end of the outer cavity 1, and a metal cover plate 3 is arranged at the upper end of the upper cavity 2, an inner conductor 5 is arranged inside the outer cavity 1, and the surface of the inner conductor 5 is arranged between the outer cavity 1 and the upper cavity 2, and a gap is arranged between the outer cavity 1 and the inner conductor 5, a radio frequency connector 7 is arranged on the outside of the inner conductor 5, and the radio frequency connector 7 is arranged in an "N" type; a coaxial body 10 is arranged at the upper end of the radio frequency connector 7 through an installation head 9, and a microwave atmospheric pressure plasma jet unit is arranged inside the coaxial body 10, and the microwave atmospheric pressure plasma jet unit is provided with a conductor column 15, and the conductor column 15 is embedded in the coaxial body 10, and the outer A microwave source 4 is provided at the lower end of the cavity 1, and the upper end of the microwave source 4 is connected to the inner conductor 5, and the outer side of the inner conductor 5 is fixedly installed on the inner side of the outer cavity 1 and the upper cavity 2 through a supporting medium 6, and the shape of the inner conductor 5 is a stepped impedance transformation structure with different diameters, and an isolation dielectric plate 8 is provided inside the upper cavity 2, and the conductor probe of the isolation dielectric plate 8 is embedded in the inner conductor 5, and the lower end of the coaxial body 10 is connected to the mounting head 9 through a coaxial connecting end, and the left and right sides of the coaxial body 10 are provided with a conductive probe. The gas hole 11 is provided with a working medium 12 inside the gas guide hole 11, and the lower end of the working medium 12 is connected to the gas cylinder, the upper end of the coaxial body 10 is provided with an open hole Teflon layer 14 inside, and the upper end of the coaxial body 10 is threadedly installed with a top rotating cover 13, the upper end of the conductor column 15 is provided with a discharge tip 16, and the upper end of the discharge tip 16 is provided with a dielectric layer 17, and the middle end of the conductor column 15 passes through the inside of the open hole Teflon layer 14, and the lower end of the conductor column 15 is connected to the upper end of the mounting head 9;

[0038] The microwave source 4 at the lower end of the device is connected to the power divider, and then the working fluid 12 is injected from the two air guide holes 11, and the microwave source 4 is turned on. The microwave energy is evenly distributed to each plasma jet array unit through the power divider and focused on the annular gap at the upper end of the device, so that the electric field intensity here is very high. The output power of the microwave source 4 is adjusted. When it reaches a certain value, the electric field intensity at the tip annular gap breaks through the nearby gas to generate plasma. Because the device uses a gradient structure to excite plasma, the microwave power required for excitation is low, so the plasma temperature in the electromagnetic wave is low, and the plasma jets of multiple jet units can process a larger area. The design of the power divider and the isolation structure in the outer cavity 1 and the upper cavity 2 ensures that the properties of each plasma jet are consistent. The discharge tip 16 of the conductor column 15 of the jet unit is detachable, and a suitable discharge tip 16 can be replaced according to the frequency of the microwave source 4; an open-hole Teflon layer 14 is arranged near the upper end between the conductor column 15 and the coaxial body 10 to assist in constraining the airflow, stabilize the flow of the airflow to a certain extent, and make the airflow at the tip more stable, so that the plasma beam can be stably output.

[0039] Embodiment 2: Figure 1-Figure 7 The technical solution shown in the embodiment is based on the first embodiment. In order to solve the problem of being blocked and unable to be used, the following is disclosed: a servo motor 18 is fixedly installed on the upper end of the metal cover plate 3, and a first bevel gear 19 is fixedly installed on the output end of the servo motor 18, and a second bevel gear 20 is meshingly installed on the lower end of the first bevel gear 19, and a threaded screw 21 is fixedly installed on the outer side of the second bevel gear 20, and the left and right ends of the threaded screw 21 are rotatably installed on the upper end of the metal cover plate 3 through a cross plate 22, and a movable shift block 25 is threadedly installed on the surface of the threaded screw 21, and a limited guide rod 23 is installed through the front and rear ends of the movable shift block 25, and the left and right ends of the limited guide rod 23 are fixed The metal cover plate 3 is fixedly installed on the inner side of the horizontal plate 22, a column plate 24 is fixedly installed on the upper end of the metal cover plate 3, and a rotating rod 27 is rotatably installed on the upper end of the column plate 24, and a contact plate 28 is fixedly installed on the middle end of the rotating rod 27, and a sealing adjustment block 26 is sleeved inside the contact plate 28, and the lower end of the sealing adjustment block 26 is rotatably installed on the upper end of the movable shift block 25, a groove positioning plate 29 is fixedly installed on the inner side of the coaxial body 10, and a knocking protrusion plate 30 is slidably connected to the inner side of the groove positioning plate 29, and a vibration spring 31 is arranged between the front and rear ends of the knocking protrusion plate 30 and the inner side of the coaxial body 10, and the inner side of the knocking protrusion plate 30 corresponds to the contact plate 28;

[0040] When the device is working, the servo motor 18 is started, and the first bevel gear 19 and the second bevel gear 20 at the output end thereof are meshed. As the servo motor 18 is started, the second bevel gear 20 drives the threaded screw 21 to rotate. When the threaded screw 21 rotates on the inner side of the cross plate 22, it can drive the movable shift block 25 threadedly connected on its surface. Under the limit of the limit guide rod 23, the movable shift block 25 can drive the movable shift block 25 to move left and right as the threaded screw 21 rotates. When the movable shift block 25 moves, it drives the sealing adjustment block 26 rotating at the upper end, and the sealing adjustment block 26 pulls the outer connection The contact plate 28 can be rotated along the column plate 24 under the setting of the rotating rod 27. Therefore, with the movement of the movable dial block 25, under the movement of the sealing adjustment block 26, the upper end of the contact plate 28 is driven to contact the knocking protrusion plate 30. After being squeezed by the contact plate 28, the knocking protrusion plate 30 knocks on the coaxial body 10 along the groove positioning plate 29. Under the setting of the vibration spring 31, the knocking effect can be improved, the efficiency of the vibration is guaranteed, and the anti-blocking effect is achieved, so as to avoid the internal blockage of the coaxial body 10 due to impurities when the output frequency is output, thereby ensuring the use efficiency of the device and avoiding the device from being unable to be used due to impurities.

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A microwave atmospheric pressure plasma jet array based on a power divider, comprising an outer cavity (1) and an upper cavity (2) arranged at the upper end of the outer cavity (1), and a metal cover plate (3) is arranged at the upper end of the upper cavity (2); Features: An inner conductor (5) is arranged inside the outer cavity (1), and the surface of the inner conductor (5) is arranged between the outer cavity (1) and the upper cavity (2), and a gap is arranged between the outer cavity (1) and the inner conductor (5), and a radio frequency connector (7) is arranged on the outer side of the inner conductor (5), and the radio frequency connector (7) is arranged in an "N" shape; The upper end of the radio frequency connector (7) is provided with a coaxial body (10) through a mounting head (9), and a microwave atmospheric pressure plasma jet unit is provided inside the coaxial body (10), and the microwave atmospheric pressure plasma jet unit is provided with a conductor column (15), and the conductor column (15) is embedded inside the coaxial body (10).

2. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 1, characterized in that: A microwave source (4) is provided at the lower end of the outer cavity (1), and the upper end of the microwave source (4) is connected to the inner conductor (5), and the outer side of the inner conductor (5) is fixedly mounted on the inner side of the outer cavity (1) and the upper cavity (2) via a supporting medium (6).

3. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 2, characterized in that: The inner conductor (5) is in the shape of a stepped impedance transformation structure with different diameters; an isolation dielectric plate (8) is provided inside the upper cavity (2); and a conductor probe of the isolation dielectric plate (8) is embedded inside the inner conductor (5).

4. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 1, characterized in that: The lower end of the coaxial body (10) is connected to the mounting head (9) via a coaxial connecting end, and air guide holes (11) are provided on the left and right sides of the coaxial body (10), and a working medium (12) is provided inside the air guide hole (11), and the lower end of the working medium (12) is connected to a gas cylinder.

5. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 4, characterized in that: An open-pored Teflon layer (14) is provided inside the upper end of the coaxial body (10), and a top rotating cover (13) is threadedly mounted on the upper end of the coaxial body (10).

6. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 5, characterized in that: The upper end of the conductor post (15) is provided with a discharge tip (16), and the upper end of the discharge tip (16) is provided with a dielectric layer (17), and the middle end of the conductor post (15) penetrates the inside of the perforated Teflon layer (14), and the lower end of the conductor post (15) is connected to the upper end of the mounting head (9).

7. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 1, characterized in that: A servo motor (18) is fixedly mounted on the upper end of the metal cover plate (3), a first bevel gear (19) is fixedly mounted on the output end of the servo motor (18), a second bevel gear (20) is meshedly mounted on the lower end of the first bevel gear (19), and a threaded screw (21) is fixedly mounted on the outer side of the second bevel gear (20).

8. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 7, characterized in that: The left and right ends of the threaded screw (21) are rotatably mounted on the upper end of the metal cover plate (3) via a transverse plate (22); a movable shifting block (25) is threadedly mounted on the surface of the threaded screw (21); and a limit guide rod (23) is installed through the front and rear ends of the movable shifting block (25); and the left and right ends of the limit guide rod (23) are fixedly mounted on the inner side of the transverse plate (22).

9. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 8, characterized in that: A column plate (24) is fixedly mounted on the upper end of the metal cover plate (3), a rotating rod (27) is rotatably mounted on the upper end of the column plate (24), a contact plate (28) is fixedly mounted on the middle end of the rotating rod (27), a sealing adjustment block (26) is sleeved inside the contact plate (28), and the lower end of the sealing adjustment block (26) is rotatably mounted on the upper end of the movable shift block (25).

10. The microwave atmospheric pressure plasma jet array based on a power divider according to claim 9, characterized in that: A groove positioning plate (29) is fixedly installed on the inner side of the coaxial body (10), and a knocking lug plate (30) is slidably connected to the inner side of the groove positioning plate (29), and a vibration spring (31) is arranged between the front and rear ends of the knocking lug plate (30) and the inner side of the coaxial body (10), and the inner side of the knocking lug plate (30) corresponds to the contact plate (28).

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