Patent ID: 6051807
Filing Date: 2000-04-18
Classification: B23K

Abstract:
A pulse arc welding apparatus for arc-welding by feeding a consumable electrode at a constant rate, and by applying a welding current constituted of a pulse current of a constant voltage characteristic and a base current of a constant current characteristic between the consumable electrode and a work piece, comprising:a pulse voltage detecting means for detecting a pulse voltage;a pulse voltage setting means for setting a pulse voltage;a pulse current control means for outputting a pulse current command value, based on a different signal between said pulse voltage detecting means and said pulse voltage setting means;a pulse current detecting means for detecting a pulse current;a pulse current setting means for setting a pulse current;a pulse frequency control means for outputting a pulse frequency command value, based on a different signal between said pulse current detecting means and said pulse current setting means;a pulse current upper and lower limit values setting means for outputting at least one of a pulse current upper limit value and a pulse current lower limit value;a pulse current comparison and adjustment means for inputting a pulse current command value and at least one of a pulse current upper limit value and a pulse current lower limit value, for outputting said pulse current upper limit value when said pulse current upper limit value is input and said pulse current command value is larger than said pulse current upper limit value, and said pulse current lower limit value when said pulse current lower limit value is input and said pulse current command value is less than said pulse current lower limit value, and for outputting said pulse current command value in a case except the above; anda pulse frequency correction means for outputting a frequency correction value f.sub.e to said pulse frequency control means, such that when said pulse current upper limit value or lower limit value is selected continuously a predetermined number of times at said pulse current comparison and adjustment means, said pulse frequency is increased/decreased by a predetermined value .DELTA.f in accordance with said selected number of times.