Arc welding set with power source and inverter
AssigneesL'Air Liquide, Societe Anonyme a Directoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges Claude, La Soudure Autogene Francaise
InventorPeyofougou Coulibaly
Life of this patent
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Abstract
A welding machine with a power source and an inverter. The inverter has at least one switching leg, made up of switches in series, and an output terminal. The power source has a circuit for controlling the switches by delivering an on-signal or and off-signal. The power source also has a transformer linked to a rectifier. The power source also has a circuit for detecting the voltage that the terminals of each switch of the inverter. A pilot circuit is also present for receiving control and voltage signals. The pilot circuit then sends a pilot circuit to each of the switches. The pilot signal corresponds to an on-command when the control signal corresponds to an on-signal and when the voltage between the power electrodes is very close to zero.
Claims7
An apparatus which may be used for welding, said apparatus comprising:
- a) a quasi-resonant soft-switching inverter, wherein said inverter comprises:
- 1) a connection means to a first power source, wherein said first power source comprises:
- i) a DC voltage power supply terminal;
- and
- ii) a reference terminal;
- and
- 2) at least one quasi-resonant type switching leg, wherein each said leg comprises:
- i) an even number of switches connected in series between said first power source and said reference terminal, wherein;
- aa) each said switch is connected in parallel to a capacitive element;
- and
- bb) each said switch is connected in series to an inductive element forming resonance element;
- and
- ii) an output terminal, wherein said output terminal is located between the two central switches of said leg;
- and
- b) an apparatus power source, wherein said apparatus power source comprises:
- 1) a control circuit for said switches, wherein:
- i) said control circuit sends a control signal;
- and
- ii) said control signal comprises at least one member selected from the group consisting of:
- aa) an on-signal;
- and
- bb) an off-signal;
- 2) a transformer, wherein said transformer comprises:
- i) a primary element linked to said output terminal;
- and
- ii) a secondary element linked to a rectifier, wherein said rectifier delivers a power source output DC voltage;
- 3) a detection circuit, wherein:
- i) said detection circuit detects the voltage between the power electrodes of each said switch;
- and
- ii) said detection circuit sends a detection voltage signal;
- and
- 4) a pilot circuit, wherein:
- i) said pilot circuit receives said control signal and said voltage signal;
- and
- ii) said pilot circuit sends a pilot signal to each said switch, wherein said pilot signal comprises at least one member selected from the group consisting of:
- aa) an off-signal corresponding to a first set of conditions, wherein said first set of conditions comprises at least one member selected from the group consisting of:
- aaa) said control signal is an off-signal;
- and
- bbb) said voltage between said electrodes is substantially non-zero;
- and
- bb) an on-signal corresponding to a second set of conditions, wherein said second set of conditions comprises:
- aaa) said control signal is an on-signal;
- and
- bbb) said voltage between said electrodes is substantially zero.
Dependencies are inferred from the claim text.