RU2418341C1 - Device for heating of electrodes and creation of self-sustained arc discharge with ignition from thin metal wire - Google Patents

Abstract

FIELD: electricity. ^ SUBSTANCE: between electrodes at fixed distance between them there supplied is voltage; appearing current melts and evaporates thin wire which is arranged between electrodes; distance between electrodes is chosen so that discharge does not occur spontaneously without wire, and conditions for avalanche breakdown of discharge gap are created between electrodes. At that, electrodes are placed in chamber with holes for suction and passage of gas through discharge gap and serve as heat source at combustion of metal of electrodes in air. ^ EFFECT: development of self-sustained arc discharge. ^ 1 dwg

Description

The invention relates to the field of studying the physical properties of a substance, in particular, to studying processes in a plasma and in gas-discharge devices, between which the voltage is applied between the anode and cathode at a fixed distance between them. The resulting current melts and evaporates a thin wire that is placed between the electrodes in contact with them. The distance between the electrodes is chosen so that a discharge without a wire does not occur. Between the electrodes, conditions are created for an avalanche breakdown of the discharge gap. The electrodes themselves are placed in a chamber with holes for suction and gas flow through the discharge gap and serve as a source of heat during the combustion of metal electrodes in air.

The technical result of the invention is the development of a method of heating electrodes and ignition of an independent arc discharge with ignition from a thin metal wire.

A device is known for heating the electrodes and creating an arc discharge when voltage is applied between the electrodes that are stationary relative to each other due to the explosion of a thin wire located between them [1].

This device does not allow to heat the electrodes and receive an independent arc discharge.

A device for heating the cathode and ignition of an arc discharge due to the initial close contact of moving relative to each other electrodes with their subsequent dilution.

This device does not allow heating the cathode and igniting an arc discharge in the discharge gap between the stationary electrodes [2].

The technical problem solved in the proposed invention is to develop a device for heating the electrodes and creating an independent arc discharge during melting and evaporation of the wire inside the discharge gap when the electrodes are placed in the chamber with holes for suction and gas flow through the discharge gap, which allows heat to be generated during combustion metal electrodes in the air.

The problem is achieved in that between the anode and cathode at a fixed distance between them, a thin metal wire melts and evaporates. In this case, the electrodes are heated and an independent arc discharge is ignited in the case when the electrodes are placed in a chamber with holes for suction and gas flow through the discharge gap and serve as a heat source during the combustion of metal electrodes in air.

This device for the first time makes it possible to heat the electrodes and ignite an independent arc discharge in the gap with the distance between the electrodes, at which it does not spontaneously ignite without a wire and without a chamber with holes for suction and ensuring the gas flow through the discharge gap.

The essence of the device is as follows. A thin metal wire is placed between the electrodes, in contact with them. In this case, the distance between the electrodes is chosen such that the arc does not spontaneously form. The electrodes are supplied with voltage from the source. The resulting electric current melts and evaporates the wire. Between the electrodes, conditions are created for an avalanche breakdown of the discharge gap. In the event that the electrodes are placed in a chamber with openings for suction and gas flow through the discharge gap, the oxidation of the metal in a confined space produces additional heating of the electrodes and an independent arc discharge arises between them, and the metal vapor to maintain the discharge comes from the hot electrodes themselves . The electrodes are heated and an independent arc discharge arises between the electrodes.

The device diagram is shown in the drawing. Between the electrodes 1, a wire 2 is pulled in contact with the electrodes, the electrodes are placed inside the chamber 3, through which a stream of air flows by gravity. The voltage from the source is applied to the electrodes. A constant voltage source of 240 V was used, as well as an alternating voltage source with a frequency of 50 Hz and a maximum voltage of 380 V. Various metal electrodes were used (Cu, Ni, Fe, brass, stainless steel and others). We took wires of various metals and alloys (Cu, Ni, Fe, nichrome, Kovar, and others). The thickness of the wires varied in the range of 0.07-0.15 mm, their length varied from 10 to 30 mm.

When voltage is applied between the anode and the cathode with a wire stretched between them, the electrodes are heated, and an independent arc discharge occurs in the atmosphere if the electrodes are placed in a chamber with holes for suction and air flow through the discharge gap and serve as a heat source for the combustion of metal electrodes in the air.

In the absence of a wire between the electrodes, the discharge does not occur due to the high breakdown voltage. So, at atmospheric pressure in air at a distance between the electrodes of 10 ^-2 m, breakdown occurs at a voltage of 3.1 · 10 ⁴ V [3]. In the presence of a wire, but in the absence of a chamber with holes for suction and air flow through the discharge gap between the electrodes, a short-term non-self-sustained discharge occurs [1].

Thus, in the proposed device, for the first time, a solution was given to heating the electrodes and creating an independent arc discharge during melting and evaporation of the wire in the discharge gap if the electrodes are placed in a chamber with holes for suction and gas flow through the discharge gap and serves as a heat source during combustion metal electrodes in the air. The device can be used in engineering, for example, in the welding industry.

The device is easy to implement and efficient. It can be used in engineering and in research.

Information sources

1. R.N. Kuzmin, N.A. Miskinova, B.N. Shvilkin. Application for invention No. 2008112377 (there is a positive decision on the grant of a patent).

2. Theory of welding processes, editor V.V. Frolov. M .: "Higher School", 1988.

3. Radiophysical electronics, editor N. A. Kaptsov. MSU Publishing House, 1960, p. 497.

Claims (1)

A device for heating the electrodes and creating an independent arc discharge with ignition from a thin metal wire in air, in which voltage is applied between the electrodes at a fixed distance between them, the resulting current melts and evaporates the thin wire that is placed between the electrodes, and the distance between the electrodes is chosen such at which the discharge does not ignite spontaneously without wire, and conditions are created between the electrodes for avalanche breakdown of the discharge gap, while s are placed in a chamber with openings for the suction duct and ensuring air through the discharge gap and serve as the heat source for the metal electrodes in the combustion air.