RU181459U1 - Low temperature plasma generator - Google Patents

Abstract

The utility model relates to the electronics industry and can be used to create devices for generating low-temperature nonequilibrium plasma at atmospheric pressure. The required technical result, which consists in simplifying the setting of the operating mode, simplifying the design and reducing its overall dimensions, is achieved in a device made in the form of a dielectric tube fixed in a rigid casing, forming an ionization chamber, inside which a piezotransformer is installed, made with the possibility of feeding it to its input the end of the low-voltage alternating voltage, converted into a high-voltage voltage on the discharge electrode - the output end of the piezotransformer, as well as a dielectric cap tightly fitting the output end of the piezotransformer. 1 s.p. f-ly; 1 ill.

Description

The utility model relates to the electronics industry and can be used to create devices for generating low-temperature nonequilibrium plasma at atmospheric pressure, in particular for use in plasma-chemical sources that activate a gas medium with the possibility of surface treatment of various, including thermally unstable materials.

A device for generating plasma is known [RU 2285348, C2, H05H 1/00, H05H 1/24, 10/10/2006] containing a nozzle with a rod electrode pointed at the end connected to a source of a plasma-forming substance, and an output electrode with a through channel for creating electric field from the side of the nozzle exit channel, while the end of the rod electrode extends beyond the nozzle by a distance exceeding two diameters of the nozzle exit channel, and the distance between the nozzle exit hole and the output electrode is from three to The diameter of the hole in the nozzle channel.

The disadvantage of this device is its relatively high complexity, since it can only be used in combination with a device that provides a working gas flow.

The closest technical solution, selected as a prototype, is a device [RU 167545, U1, Н05Н 1/24, 01/10/2017] containing a high-voltage transformer with a discharge electrode in the secondary circuit, located in the ionization chamber, to the input of which the primary power generator is connected high voltage transformer circuit and gas mixture forming device, nozzle at the exit of the ionization chamber, voltage control unit connected to the primary low voltage circuit of the high voltage transformer, compressor connected to about the input of the device for forming a gas mixture containing elements for adjusting the composition of the gas mixture, while in the area of the nozzle exit there are devices of magnetic and electrical effects, and the discharge electrode is made pointed.

A feature of the closest technical solution is that the high-voltage transformer is made in the form of a piezotransformer, the gas mixture forming device contains a gas mixture source connected in output to a gas mixer, the second input of which is connected to the compressor output through a choke, and the gas mixer output is connected to an ionization chamber , the tip of the discharge electrode is provided with needles in the form of a brush, and the tip of the discharge electrode is made in the form of a funnel.

The disadvantage of the closest technical solution is the relatively high complexity of setting the operating mode and the relatively high complexity of the design, since it can only be used in combination with a device that provides a flow of working gas, as well as relatively large overall dimensions.

The problem that is solved in the utility model is to create a generator characterized by a simpler adjustment of the operating mode, a simpler design and having smaller overall dimensions. With the ability to work both in the flow of the working gas, and in the mode without gas flow.

The required technical result is to simplify the adjustment of the operating mode, simplify the design and reduce its overall dimensions, as well as the possibility of working without a working gas channel.

The problem is solved, and the required technical result is achieved by the fact that, in the low-temperature plasma generator, made in the form of a dielectric tube fixed in a rigid housing forming an ionization chamber, inside which a piezotransformer is installed, configured to supply low-voltage alternating voltage to its input end according to the utility model, a dielectric cap is inserted into the high-voltage voltage at the output end of the piezotransformer, which fits the exit hydrochloric end piezotransformer.

In addition, the required technical result is achieved in that the inlet end of the dielectric tube is equipped with means for pumping the working gas from the inlet end to the outlet end of the dielectric tube, moreover, the outlet end of the dielectric tube is plastic and equipped with means for changing its shape.

The drawing shows a functional diagram of a low-temperature plasma generator with a low-voltage alternating voltage generator and means for changing the shape of the output end of the dielectric tube.

In the drawing are indicated:

1 - piezotransformer;

2 - discharge electrode;

3 - ionization chamber;

4 - dielectric tube;

5 - hard case;

6 - low voltage alternator

7 - output end of the dielectric tube;

8 - means for changing the shape of the output end of the dielectric tube;

9 - a cap of a dielectric;

10 - dielectric.

The low-temperature plasma generator is made in the form of a dielectric tube 4 fixed in a rigid body 5, forming an ionization chamber 3, inside which a piezotransformer 1 is installed, configured to supply a low-voltage alternating voltage to its input end, for example, from a low-voltage alternating voltage generator 6, which is converted to high-voltage voltage on the discharge electrode 2, made at the output end of the piezotransformer 1.

In addition, the low-temperature plasma generator contains a cap 9 of dielectric, tightly fitting the output end of the piezotransformer 1, which allows you to change the thickness of the layer of dielectric 10, which allows you to work in the barrier discharge mode with the creation of a nonequilibrium air plasma at a close distance from the outer dielectric layer, for example, 1 -3 mm.

In the low-temperature plasma generator, the input end of the dielectric tube 4 can be equipped with means for pumping working gas (not shown) from the input end to the output end of the dielectric tube 4, and the output end of the dielectric tube 4 can be made plastic and equipped with means 8 for changing its shape.

A low-temperature plasma generator operates as follows.

The generator is designed to create a device for generating low-temperature nonequilibrium plasma at atmospheric pressure and can be used to create plasma-chemical sources that activate a gas environment with the possibility of surface treatment of various materials.

Nonequilibrium plasma is formed in the discharge (smoldering, arc, radio frequency, barrier, etc.) and is ejected through a narrow nozzle (round or slotted in cross section) due to the creation of an excess pressure in the discharge zone that exceeds atmospheric pressure.

Excitation by a glow, corona, or barrier discharge creates a plasma with an average gas temperature of 20 to 60 ° C and a charged particle density typical of weakly ionized gases and an active particle concentration of up to 100 ppm. To obtain a plasma, voltage pulses of positive and negative polarity are used, with a duration of the order of 0.1-1 μs, an amplitude of up to 5 kV, and a repetition rate of tens of kHz. A nonequilibrium plasma with an average temperature close to room temperature is formed at atmospheric pressure without pumping the working gas using a surface barrier barrier when working with a cap 9 made of a dielectric. The plasma arises due to a barrier discharge at the surface of the dielectric 10. Processing occurs when the cap approaches a distance of 1-2 mm from the surface being treated.

It is possible to use a generator using a piezoelectric discharge in the case of pumping working gas when using means for pumping working gas from the inlet to the output end of the dielectric tube with gas pumping speeds from units to tens of 1 / min.

Means 8 can be used to change the shape of the output end of the dielectric tube 4 (shape of the output nozzle of the generator). The inlet end of the dielectric tube 4 may be equipped with means for pumping the working gas from the inlet to the outlet end of the dielectric tube. In this case, it is possible to treat the surface of the product with a thin jet of low-temperature plasma in an atmosphere of argon or helium, or use a barrier-surface discharge in air without pumping the working gas.

Thus, thanks to the introduced improvements, the required technical result is achieved, which consists in simplifying the adjustment of the operating mode (by using a cap) and simplifying the design and in reducing the overall dimensions (due to the lack of means for pumping the working gas). Moreover, the proposed design allows, if necessary, to use the generator in the mode of pumping working gas.

Claims (2)

1. The low-temperature plasma generator, made in the form of a dielectric tube fixed in a rigid body, forming an ionization chamber, inside which a piezotransformer is installed, configured to supply a low-voltage alternating voltage to its input end, which is converted to a high-voltage voltage on the discharge electrode, the output end of the piezotransformer, characterized the fact that the cap is made of a dielectric, tightly fitting the output end of the piezotransformer. 2. The low-temperature plasma generator according to claim 1, characterized in that the input end of the dielectric tube is equipped with means for pumping the working gas from the input end to the output end of the dielectric tube, the output end of the dielectric tube being plastic and equipped with means for changing its shape.

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