Pulse arc welding machine

Claim 1

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding said wire electrode to said welding torch; supplying a base current between said wire electrode and said pulse material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit time of said pulse current in proportion to a speed of feeding said wire electrode; wherein, in said steps of supplying said base current and supplying said pulse current, a peak value of a composite current of said base current and said pulse current is set so that a quantity of heat applied to said wire electrode and a molten drop diameter formed, for soft steel, are determined by: ______________________________________ Wire diameter Optimum molten drop Optimum heat d (mm .0.) diameter range (mm .0.) quantity range (J) ______________________________________ 0.9 0.99-1.43 4.96-14.6 1.2 1.14-1.44 7.4-15.1 1.6 1.24-1.46 9.4-15.7 ______________________________________

Claim 2

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding said wire electrode to said welding torch; supplying a base current between said wire electrode and said pulse material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit time of said pulse current in proportion to a speed of feeding said wire electrode; wherein, in said steps of supplying said base current and supplying said pulse current, a peak value of a composite current of said base current and said pulse current is set so that a quantity of heat applied to said wire electrode and a molten drop diameter formed, for soft steel, are determined by: ______________________________________ Wire diameter Optimum molten drop Optimum heat d (mm .0.) diameter range (mm .0.) quantity range (J) ______________________________________ 0.9 0.99-1.43 4.96-14.6 1.2 1.14-1.44 7.4-15.1 1.6 1.24-1.46 9.4-15.7 ______________________________________

Claim 3

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding said wire electrode to said welding torch; supplying a base current between said wire electrode and said pulse material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit time of said pulse current in proportion to a speed of feeding said wire electrode; wherein, in said step of feeding said wire electrode to said welding torch and in said step of applying said pulse current, a ratio of an optimum wire feeding speed to a number of pulses of said pulse current is determined by: ______________________________________ Ratio of optimum wire feeding speed Wire diameter to number of pulses d (mm) (cm/pulse) ______________________________________ 0.9 0.080-0.241 1.2 0.068-0.138 1.6 0.050-0.081 ______________________________________

Claim 4

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding said wire electrode to said welding torch; supplying a base current between said wire electrode and said pulse material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit time of said pulse current in proportion to a speed of feeding said wire electrode; wherein, in said step of feeding said wire electrode to said welding torch and in said step of applying said pulse current, a ratio of an optimum wire feeding speed to a number of pulses of said pulse current is determined by: ______________________________________ Ratio of optimum wire feeding speed Wire diameter to number of pulses d (mm) (cm/pulse) ______________________________________ 0.9 0.080-0.241 1.2 0.068-0.138 1.6 0.050-0.081 ______________________________________

Claim 5

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is soft steel wire having a diameter of 1.2 mm and said shielding gas comprises Ar and CO 2 in a ratio of 8:2, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧370A, and 1.2/τ≦I.sub.p ≦2.42/τ, where τ is a width of said pulses in milliseconds.

Claim 6

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is soft steel wire having a diameter of 1.2 mm and said shielding gas comprises Ar and CO 2 in a ratio of 8:2, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧370A, and 1.2/τ≦I.sub.p ≦2.42/τ, where τ is a width of said pulses in milliseconds.

Claim 8

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is soft steel wire having a diameter of 1.6 mm and said shielding gas comprises Ar and CO 2 in a ratio of 8:2, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧550A, and

Claim 9

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is soft steel wire having a diameter of 1.6 mm and said shielding gas comprises Ar and CO 2 in a ratio of 8:2, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧550A, and

Claim 13

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is soft steel wire having a diameter of 0.9 mm and said shielding gas comprises Ar and CO 2 in a ratio of 8:2, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧250A, and

Claim 14

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is soft steel wire having a diameter of 0.9 mm and said shielding gas comprises Ar and CO 2 in a ratio of 8:2, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧250A, and

Claim 19

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is stainless steel wire having a diameter of 1.2 mm and said shielding gas comprises Ar and CO 2 in a ratio of 97:3, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧270A, and

Claim 20

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is stainless steel wire having a diameter of 1.2 mm and said shielding gas comprises Ar and CO 2 in a ratio of 97:3, and a peak value I p of said pulse current is set in accordance with: I.sub.p ≧270A, and

Claim 23

The method as claimed in either of claims 3 and 10, wherein an optimum molten drop diameter range for said wire electrode is 1.14-1.44 mm, and an optimum heat quantity range applied to said wire electrode is 7.4-15.1 Joules.

Claim 24

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is aluminum wire having a diameter of 1.6 mm and said shielding gas comprises Ar, and a peak value I p of said pulse current is set in accordance with: 27≦ I.sub.p ≦400A, and 0.65/τ≦I.sub.p ≦1.27/τ, where τ is a width of said pulses in milliseconds.

Claim 25

A method for operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and base material; supplying a pulse current between said wire electrode and said base material; and varying a number of pulses per unit of time of said pulse current in proportion to a feeding speed of said wire electrode; wherein, said wire electrode is aluminum wire having a diameter of 1.6 mm and said shielding gas comprises Ar, and a peak value I p of said pulse current is set in accordance with: 27≦ I.sub.p ≦400A, and 0.65/τ≦I.sub.p ≦1.27/τ, where τ is a width of said pulses in milliseconds.

Claim 26

The method as claimed in either of claims 5 and 12, wherein the ratio of said wire electrode feeding speed to said number of pulses is 0.050-0.081 cm per pulse.

Claim 27

A method of operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and said base material; supplying a pulse current between said wire electrode and said base material; and varying the number of pulses per unit time of said pulse current in proportion to a feeding speed of said wire electrode; wherein said wire electrode has a diameter in a range of 0.9 to 1.6 mm, and said shielding gas comprises at least Ar, and wherein a peak value I p of said pulse current is set in accordance with: I.sub.p ≧250A, and 0.65/τ≦I.sub.p ≦2.52/τ, where τ is a width of said pulses in milliseconds.

Claim 28

A method of operating a pulse arc welding machine of a type in which a wire electrode is fed by a welding torch confronting a base material in such a manner that the wire electrode is maintained spaced from the base material, comprising the steps of: supplying a shielding gas to a welding area of said base material; feeding a wire electrode to said welding torch; supplying a base current between said wire electrode and said base material; supplying a pulse current between said wire electrode and said base material; and varying the number of pulses per unit time of said pulse current in proportion to a feeding speed of said wire electrode; wherein said wire electrode has a diameter in a range of 0.9 to 1.6 mm, and said shielding gas comprises at least Ar, and wherein a peak value I p of said pulse current is set in accordance with: I.sub.p ≧250A, and 0.65/τ≦I.sub.p ≦2.52/τ, where τ is a width of said pulses in milliseconds.