EP0043589A1 — Pulse arc welding machine

Claim 1

Independent Claim 149 words

A pulse arc welding machine comprising: a wire electrode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) for supplying a pulse current superposed on said base current flowing between said wire electrode (8) and said base material (11); a detector (29) for detecting an arc discharge voltage between said wire electrode (8) and said base material (11); and a controller (32) for comparing a detected output value from said detector (29) with a preset reference value for controlling the amount of heat applied to said wire electrode (8) such that an arc voltage between said wire electrode (8) and said base material (11) is maintained substantially at a value determined by said reference value.

Claim 2

Dependent Claim 149 words

A pulse arc welding machine comprising: a wire electrode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) for supplying a pulse current superposed on said base current flowing between said wire electrode (8) and said base material (11); a detector (29) for detecting an arc discharge voltage between said wire electrode (8) and said base material (11); and a controller (32) for comparing a detected output value from said detector (29) with a preset reference value for controlling the amount of heat applied to said wire electrode (8) such that an arc voltage between said wire electrode (8) and said base material (11) is maintained substantially at a value determined by said reference value.

Claim 3

Dependent Claim 56 words

The welding machine as claimed in claim 1 wherein said pulse current source (17) is connected between an arc section between said wire electrode (8) and said base material (11), and a DC power source (15), and comprises a switching element (17) adapted to open and close under control of a signal from said controller (32).

Claim 4

Dependent Claim 31 words

The welding machine as claimed in claim 1 wherein said controller (32) comprises means for automatically varying welding factors to control the amount of heat applied to said wire electrode (8).

Claim 5

Dependent Claim 44 words

The welding machine as claimed in claim 3 wherein said welding factor is at least one of a pulse width of said pulse current, the frequency of said pulse current, the peak-value of said pulse current, said base current and a wire feeding rate.

Claim 6

Dependent Claim 178 words

A pulse arc welding machine comprising: a wire electrode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) for supplying a pulse current superposed on said base current flowing between said wire electrode (8) and said base material (11); a detector (29) for detecting an arc discharge voltage between said wire electrode (8) and said base material (11); and a controller (32) for setting as one of functions and constants optimum values of welding factors for suitably determining a welding arc between said wire electrode (8) and said base material (11) corresponding to welding conditions determined in accordance with the diameter and the material of said wire electrode (8) and composition of a shielding gas to automatically select optimum values of said welding factors responsive to said welding conditions so as . to control the amount of heat applied to said wire electrode (8).

Claim 7

Dependent Claim 178 words

A pulse arc welding machine comprising: a wire electrode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) for supplying a pulse current superposed on said base current flowing between said wire electrode (8) and said base material (11); a detector (29) for detecting an arc discharge voltage between said wire electrode (8) and said base material (11); and a controller (32) for setting as one of functions and constants optimum values of welding factors for suitably determining a welding arc between said wire electrode (8) and said base material (11) corresponding to welding conditions determined in accordance with the diameter and the material of said wire electrode (8) and composition of a shielding gas to automatically select optimum values of said welding factors responsive to said welding conditions so as . to control the amount of heat applied to said wire electrode (8).

Claim 8

Dependent Claim 73 words

The welding machine as claimed in claim 5 wherein said controller (32) operates to set relations between a wire feeding rate and said arc voltage and comprises a function generator (3o5) for outputting a voltage corresponding to said wire feeding rate for varying the pulse width of said pulse current so that a detected value of the arc voltage of the welding arc coincides with said voltage outputted from said function generator (305).

Claim 9

Dependent Claim 61 words

The welding machine as claimed in claim 5 wherein said controller (32) operates to set relations between a wire feeding rate and said pulse frequency and comprising a function generator (3o6) for outputting a voltage corresponding to said wire feeding rate for varying the pulse frequency of said pulse current in response to said voltage output from said function generator (3o6).

Claim 10

Dependent Claim 164 words

A pulse arc welding machine comprising: a wire electode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) for supplying a pulse current superposed on said base current flowing between said wire electrode (8) and said base material (11); a detector (29) for detecting an arc discharge voltage between said wire electrode (8) and said base material (11); an arc current detecting circuit (211) for detecting an arc current flowing between said wire electrode (8) and said base material (11); and a controller (32) for controlling the amount of heat applied to said wire electrode (8) such that said arc voltage approaches a reference value in response to at least one of a detected value of said detector (29) and an output signal from said arc current detecting circuit (211).

Claim 11

Dependent Claim 164 words

A pulse arc welding machine comprising: a wire electode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) for supplying a pulse current superposed on said base current flowing between said wire electrode (8) and said base material (11); a detector (29) for detecting an arc discharge voltage between said wire electrode (8) and said base material (11); an arc current detecting circuit (211) for detecting an arc current flowing between said wire electrode (8) and said base material (11); and a controller (32) for controlling the amount of heat applied to said wire electrode (8) such that said arc voltage approaches a reference value in response to at least one of a detected value of said detector (29) and an output signal from said arc current detecting circuit (211).

Claim 12

Dependent Claim 75 words

The welding. machine as claimed in claim 8 wherein said controller (32) operates to set relations between a wire feeding rate and said arc voltage and comprises a function generator (3o5) for outputting a voltage corresponding to a wire feeding rate for varying a pulse width of said pulse current so that the detected value of the arc voltage due to the welding arc coincides with the output from said function generator (3 0 5).

Claim 13

Dependent Claim 64 words

1 0 . The welding machine as claimed in claim 8 or 9, wherein said controller (32) operates to set relations between a wire feeding rate and said pulse frequency and comprises a function generator (3o6) for outputting a voltage corresponding to said wire feeding rate for varying the frequency of said pulse current in response to an output from said function generator (3o6).

Claim 14

Dependent Claim 76 words

The welding machine as claimed in claim 8 or 9 wherein said controller (32) operates to set relations between a wire feeding rate and said arc voltage and comprises a function generator (306) for outputting a voltage corresponding to said wire feeding rate for varying the frequency of said pulse current so that the detected value of the arc voltage due to the welding arc coincides with the output from said function generator (3 0 6).

Claim 15

Dependent Claim 69 words

The welding machine as claimed in claim 8 or 9 wherein said controller (32) operates to set relations between a wire feeding rate and said arc voltage and comprises,a function generator (3oG) for outputting a voltage corresponding to said wire feeding rate for varying the peak value of said pulse current so that the detected value of the arc voltage coincides with said output from said function generator (3o6).

Claim 16

Dependent Claim 61 words

The welding machine as claimed in claim 8 or 9 wherein said controller (32) operates to set relations between a wire feeding rate and said arc voltage and comprises a function generator for outputting a voltage corresponding to said wire feeding rate for varying said base current so that the detected arc voltage coincides with an output from said function generator.

Claim 17

Dependent Claim 67 words

The welding machine as claimed in claim 8 or 9 wherein said controller (32) operates to define relations between a wire feeding rate and said arc voltage and comprises a function generator (3o5) for outputting a voltage corresponding to said wire feeding rate for varying said wire feeding rate so that the detected value of the arc voltage coincides with an output from said function generator (3o5).

Claim 18

Dependent Claim 177 words

A pulse arc welding machine comprising: a wire electrode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) having a pulse current supply and a switching element (17) for controlling opening and closing of said pulse current supply, said pulse current being superposed on said base current flowing, between said wire electrode (8) and said base material (11); an instruction signal output unit for generating a first instruction signal for setting_the pulse frequency of said pulse current to a predetermined value and a second instruction signal for maintaining . a peak value of said pulse current at a predetermined value; and a controller (32) for controlling opening and closing of said switching element (17) in accordance with said first and second instruction signals from said instruction signal output unit so as to control the amount of heat applied to said wire electrode (8).

Claim 19

Dependent Claim 177 words

A pulse arc welding machine comprising: a wire electrode (8); a wire feeding unit (9) for feeding said wire electrode (8) to a base material (11); a base current source (16) for supplying a base current flowing between said wire electrode (8) and said base material (11); a pulse current source (17) having a pulse current supply and a switching element (17) for controlling opening and closing of said pulse current supply, said pulse current being superposed on said base current flowing, between said wire electrode (8) and said base material (11); an instruction signal output unit for generating a first instruction signal for setting_the pulse frequency of said pulse current to a predetermined value and a second instruction signal for maintaining . a peak value of said pulse current at a predetermined value; and a controller (32) for controlling opening and closing of said switching element (17) in accordance with said first and second instruction signals from said instruction signal output unit so as to control the amount of heat applied to said wire electrode (8).

Claim 20

Dependent Claim 116 words

The welding machine as claimed in claim 15 wherein said instruction output unit produces said first instruction signal as an input signal to a frequency setting unit (364) for periodically opening and closing said switching element (17) and a second instruction signal as an input signal to a comparator (363) for setting said switching element (17) in an open state when a detected value of output current reaches an upper limiting current value, for setting said switching element (17) in a closed state when a detected value of said output current reaches a lower limiting current value, and for closing said switching element (17) when both said first and second instruction signals are simultaneously closure instructions.

Claim 21

Dependent Claim 37 words

The welding machine as claimed in claim 15 further comprising a diode (221) connected to said switching (17) element and an arc section (1 0 ) for circulating a dynamic current generated upon opening said switching element.

Claim 22

Dependent Claim 42 words

The welding machine as claimed in claim 17 further comprising a DC reactor (367) connected in series with said arc section (1 0 ) for reducing an opening and closing frequency of said switching element (17) set by said second instruction signal.

Claim 23

Dependent Claim 33 words

The welding machine as claimed in claim 16 wherein a difference between the upper limiting current value value and the lower limiting current value of the output current is less than 15o A.

Claim 24

Dependent Claim 28 words

2 0 . The welding machine as claimed in claim 18 wherein the value of said DC reactor (367) is in a range of 1o to 2oo µH.

Claim 25

Dependent Claim 20 words

The welding machine as claimed in any of claims 16 through 2o wherein said switching element (17) is a transistor.

Pulse arc welding machine

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag