Two-channel device for two-frequency arc welding

1 . A method of igniting an arc discharge and welding thereby; the method comprising steps of:

a. providing a two-channel device for igniting an arc discharge and welding thereby; the two-channel device comprising:

i. a first channel further comprising:

1) A power supply further comprising a power transformer; and

2) A controller of the power transformer configured to provide a reduced, arc-sustaining voltage and a full welding voltage;

ii. a second channel further comprising:

1) A high-frequency generator; and

2) A resonant circuit connected in series to the high-frequency generator;

iii. a current meter within the second channel, configured to measure a high-frequency current, wherein the measured high-frequency current provides an indication of a degree of ionization of a contact zone between an electrode and an article to be welded, and wherein the controller is configured to automatically apply the full welding voltage after a variable delay, the delay being determined in response to the measured high-frequency current; and

iv. output terminals connectable to an electrode and a welding stand; the first and second channels are connectable to the output terminals in parallel;

b. placing articles to be welded onto the welding stand;

c. connecting the electrode and welding stand to the output terminals;

d. contacting the electrode with at least one of the articles to be welded;

e. applying a high-frequency voltage generated by the high-frequency generator to the electrode while simultaneously providing the reduced, arc-sustaining voltage from the power transformer, thereby causing a combined current from both channels to heat an area of contact; and

f. after the variable delay, determined based on the measured high-frequency current, applying the full welding voltage from the power transformer to the electrode to establish a dual-frequency welding arc.

2 . The method according to claim 1 , further comprising rectifying an output of the first channel with a power rectifier and rectifying an output of the second channel with a high-frequency rectifier to provide a dual-frequency current for welding.

3 . The method according to claim 1 , wherein the power transformer has an open-circuit output voltage ranging between 30 and 32V.

4 . The method according to claim 1 , wherein the high-frequency voltage is a rectangular voltage ranging between 40 and 60V at frequency ranging between 35 and 40 kHz and power ranging between 250 and 300 W.

5 . The method according to claim 1 , wherein a duration of the delay between the application of the reduced, arc-sustaining voltage and the restoration of the full welding voltage is automatically determined based on a degree of ionization of the contact zone, as indicated by a high-frequency current measured by the current meter, and wherein the duration is in a range between 1 and 2 seconds.

6 . A two-channel device for igniting an arc discharge and welding thereby; the two-channel device comprising:

a. a first channel further comprising:

i. a power supply further comprising a power transformer; and

ii. a controller configured to operate the power transformer initially at a reduced, arc-sustaining voltage, and subsequently to restore a full welding voltage;

b. a second channel further comprising:

i. a high-frequency generator; and

ii. a resonant circuit connected in series with the high-frequency generator; and

iii. a current meter configured to measure a high-frequency current associated with a contact zone between an electrode and an article to be welded; and

c. output terminals connectable to an electrode and a welding stand, wherein said first and second channels are connected in parallel to the output terminals;

wherein the controller is configured to restore the full welding voltage after a variable delay that is automatically determined in response to the measured high-frequency current, indicative of a degree of ionization of the contact zone, such that the high-frequency generator and the reduced-voltage power transformer operate concurrently to synergistically preheat and ionize the contact zone prior to initiation of the full welding arc.

7 . The device according to claim 6 , further comprising a power rectifier connected to an output of the first channel and a high-frequency rectifier connected to an output of the second channel, wherein outputs of the rectifiers are connectable in parallel to the output terminals to provide a dual-frequency current for welding.

8 . The device according to claim 6 , wherein the power transformer has an open-circuit output voltage ranging between 30 and 32V.

9 . The device according to claim 6 , wherein the high-frequency voltage is a rectangular voltage ranging between 40 and 60V at frequency ranging between 35 and 40 kHz and power ranging between 250 and 300 W.

10 . The device according to claim 6 , wherein the variable delay prior to restoring the full welding voltage is determined based on a measured high-frequency current associated with the contact zone, the current being indicative of a degree of ionization of the contact zone, and wherein the variable delay is within a range of 1 to 2 seconds.