Adapter shaping electromagnetic field, which heats toroidal plasma discharge at microwave frequency

Abstract

The adapter shaping an electromagnetic field heats toroidal plasma discharge. It is intended for use in plasma torches dedicated for excitation/ionization sources in spectrometers. The adapter includes at least two electromagnetic field shaping elements, which are stretched between the bushing of the upper microwave connection and the bushing of the lower microwave connection. An element shaping electromagnetic field is positioned to the surface pitch of the bushings at an angle ranging from 0 to 90 degrees.

Claims

1. An adapter for shaping a microwave electromagnetic field from a microwave electromagnetic field generator, comprising a lower microwave connector bushing having a longitudinal axis removably positioned within a microwave cavity of the microwave electromagnetic field generator; an upper microwave connector bushing connected with said lower bushing in spaced coaxial relation; and at least three equally spaced identical electromagnetic field shaping elements connected in parallel with said upper and lower microwave connector bushings and arranged symmetrically within said microwave cavity between said upper and lower microwave connector bushings, wherein each electromagnetic field shaping element is positioned at an angle to a plasma surface pitch generatrix along said longitudinal axis ranging from greater than 0 degrees to 90 degrees to define a spiral configuration relative to said longitudinal axis and generate a toroidal plasma discharge within said microwave cavity by the electromagnetic field shaped by said at least three electromagnetic field shaping elements in order to heat the plasma discharge evenly from all circumferential directions relative to said longitudinal axis.

2. The adapter of claim 1, wherein said lower microwave connector bushing includes a cylindrical external connection.

3. The adapter of claim 1, wherein said upper microwave connector bushing is fixed to said lower microwave connector bushing, and wherein said at least three electromagnetic field shaping elements comprise electrically conductive rods.

4. The adapter of claim 3, wherein said upper and lower microwave connector bushings and said rods comprise a dielectric cylinder including a metal layer surface.

5. A method for using a microwave electromagnetic field shaping adapter suitable for heating a toroidal plasma discharge, the adapter comprising at least three equally spaced electromagnetic filed shaping elements connected in parallel with upper and lower microwave connector bushings and arranged symmetrically within a microwave cavity having a longitudinal axis, the at least three parallel electromagnetic field shaping elements being stretched between the upper microwave connector bushing and the lower microwave connector bushing and positioned relative to the generatrix of the upper and lower microwave connector bushings along said longitudinal axis at an angle ranging from greater than 0 degrees to 90 degrees to define a spiral configuration relative to the longitudinal axis, comprising the step of inserting the adapter as a replaceable element into a common microwave induced plasma cavity to generate a toroidal plasma discharge by the electromagnetic field shaped by said electromagnetic field shaping elements in order to heat the plasma discharge evenly from all circumferential directions relative to the longitudinal axis.

6. The method as defined in claim 5, wherein the lower microwave connector bushing includes a cylindrical external connection.

7. The method as defined in claim 5, wherein the upper microwave connector bushing is fixed with the lower microwave connector bushing and said field shaping elements comprise electrically conductive rods, respectively.

8. The method as defined in claim 7, wherein the electromagnetic field shaping elements and the upper and lower microwave connector bushings are fabricated on the surface of a dielectric cylinder as a metal layer applied by metallization.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) The invention is illustrated by figures.

(2) FIG. 1 is a schematic view of an adapter with four vertical electromagnetic field-forming elements made of electric conductive rods (wires).

(3) FIG. 2 is a schematic view of an adapter with EM field-forming elements consisting of six sections of spirals.

(4) FIG. 3 is a schematic view of an adapter with oblique electromagnetic field-forming elements consisting of four spiral components formed by cutting or applying metal cladding on a dielectric cylinder (metallization).

(5) FIG. 4 is a schematic view of an adapter with electromagnetic field-forming elements in the shape of mutually parallel rings (washers), separated by dielectric spacers.

(6) FIG. 5 is a schematic view of an adapter with electromagnetic field-forming elements in the shape of mutually parallel rings (washers), separated by dielectric spacers.

(7) FIG. 6 is a schematic view of an adapter with electromagnetic field-forming elements of the electromagnetic field shaping comprising of spiral components perpendicular to the pitch surface generation of the bushing.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

(8) An adapter for shaping microwave electromagnetic field heating toroidal plasma discharge features four mounted magnetic field-forming elements 1 between the upper bushing 2 and the lower bushing 3 or lower microwave connector. The four elements are positioned at an angle of 0 degrees to a plasma surface pitch generator or generatrix 1A along a common bushing axis 1B of the lower bushing 3 and the upper bushing 2. In this embodiment, the electromagnetic field-forming elements 1 appear as mutually parallel electrical conductive rods (wires).

Example 2

(9) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1, except here the magnetic field-forming elements are six sections of helices, inclined relatively to the pitch surface generator of the bushing 2, 3.

Example 3

(10) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1, but here the magnetic field forming elements consist of 6 parallel washers arranged at an angle of 90 degrees to the pitch surface generator of the bushing 2, 3.

Example 4

(11) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1 or Example 2, but here, the lower bushing of microwave connection 3 is equipped with an external flat connector 4, which positions the adapter within the microwave cavity.

Example 5

(12) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1 or Example 2, but the field shaping elements 1 stretched between the upper bushing of microwave connection 2 and the lower bushing of microwave connector 3 are made from a tube, where the electromagnetic field forming elements 1 are curved through milling. In addition, between the elements shaping the electromagnetic field 1, vertical cutouts 7 are made in the bushings 2, 3.

Example 6

(13) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1 or Example 2, but the elements forming the electromagnetic field 1 between the bushing upper connection of the microwaves 2 and the bushing lower connection of microwaves 3 are applied through metallization i.e. applying the metal form immediately to the surface of the dielectric cylinder.

Example 7

(14) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1 or Example 2. However, in the bushings 2, 3 between the field forming elements, vertical cuts 7 are made.

Example 8

(15) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 1 or Example 2, except that the upper bushing of the microwave connection 2 is permanently connected to the lower bushing connection of the microwave connection 3 by means of electromagnetic field forming elements 1 appearing in the shape of mutually parallel rings (washers) 8, with dielectric spacers 9 between them, where the diameters of the ring washer 8 and the spacer dielectric spacers 9 are equal.

Example 9

(16) An adapter shaping microwave electromagnetic field heating toroidal plasma discharge performs as in Example 8, except that the diameters of the ring washers 8 are larger than those of the dielectric spacers 9.

LIST OF REFERENCES IN FIGURES

(17) 1. field forming element, 2. bushing of upper microwave connection, 3. bushing of lower microwave connection, 4. external flat connection, 5. isolator layer, 6. microwave cavity, 7. the cut, 8. ring washer, 9. dielectric spacer distance washer.