US4136273A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for tig welding
Assignee: Nippon Steel Corp
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Filing: 1977-03-04
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Granted: 1979-01-23
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Expires: 1997-03-04
Abstract
Abstract A method for TIG welding by using a plurality of nonconsumable electrodes extending frm the tip of a TIG welding torch and one filler wire fed through a space between the electrodes, each electrode being independently supplied with power. A molten pool is formed by melting both the base metal to be welded and the filler wire by means of arcs generated between respective electrodes and the base metal. Melting of the base metal is mainly controlled by the arc produced by one of the plurality of electrodes while melting of the filler wire is mainly controlled by the arc generated by the other electrode.
Inventors
- 👤 Haruo Eujita
- 👤 Yasushi Ishikawa
- 👤 Hiroshi Tachikawa
- 👤 Taizo Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:35
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/16; B23K9/167; B23K9/1675
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
211 words
A method of TIG welding in which a plurality of spaced nonconsumable electrodes extending from the head of a welding torch are placed in a protective atmosphere formed by inert shielding gas emitted from the head of the welding torch which can travel along a weld line of base metal, and a filler wire is also fed into the protective atmosphere to carry out welding of the base metal, which method comprises: projecting the plurality of nonconsumable electrodes from the head of the welding torch toward the weld line; passing the filler wire at least once around a ring-shaped passage for giving it a permanent set, and then passing the filler wire through the space between the electrodes extending from the head of the welding torch for feeding the filler wire, the filler wire bending toward one of the electrodes due to the permanent set; supplying welding voltage and current independently to the respective electrodes; producing a single molten pool by melting the base metal and filler wire with arcs generated between each electrode and the base metal, and; controlling weld penetration and fusion of the base metal chiefly with arc plasma from one of the nonconsumable electrodes and melting the filler wire chiefly with arc plasma from the remaining electrodes.
Claim 2
Independent Claim
211 words
A method of TIG welding in which a plurality of spaced nonconsumable electrodes extending from the head of a welding torch are placed in a protective atmosphere formed by inert shielding gas emitted from the head of the welding torch which can travel along a weld line of base metal, and a filler wire is also fed into the protective atmosphere to carry out welding of the base metal, which method comprises: projecting the plurality of nonconsumable electrodes from the head of the welding torch toward the weld line; passing the filler wire at least once around a ring-shaped passage for giving it a permanent set, and then passing the filler wire through the space between the electrodes extending from the head of the welding torch for feeding the filler wire, the filler wire bending toward one of the electrodes due to the permanent set; supplying welding voltage and current independently to the respective electrodes; producing a single molten pool by melting the base metal and filler wire with arcs generated between each electrode and the base metal, and; controlling weld penetration and fusion of the base metal chiefly with arc plasma from one of the nonconsumable electrodes and melting the filler wire chiefly with arc plasma from the remaining electrodes.
Claim 3
Dependent Claim
88 words
A method of TIG welding according to claim 1 wherein the electric current fed to the electrode which mainly controls weld penetration of the base metal is cyclically increased and decreased in a reverse pattern of that of the electric current fed to the electrode which mainly controls melting of the filler wire, and the supply speed of the filler wire is also increased and decreased in a pattern similar to the pattern of the current fed to the electrode which mainly controls melting of the filler wire.
Claim 4
Dependent Claim
26 words
A method of TIG welding according to claim 1 wherein the plurality of nonconsumable electrodes and the filler wire are linearly positioned along the weld line.
Claim 5
Dependent Claim
24 words
A method of TIG welding according to claim 1 wherein the welding torch is weaved in directions normal to the weld line during welding.
Claim 6
Dependent Claim
26 words
A method of TIG welding according to claim 1 wherein two nonconsumable electrodes are employed and are angled inwardly toward the axis of a welding torch.
Claim 7
Dependent Claim
54 words
A method of TIG welding according to claim 1 wherein three noncomsumable electrodes are employed, one electrode being chiefly used for controlling the weld penetration of the base metal, and the other two electrodes being chiefly used for melting the filler wire, the filler wire being bent toward one of said other two electrodes.
Claim 8
Dependent Claim
29 words
A method of TIG welding according to claim 1 wherein the length and angle of each of the plurality of nonconsumable electrodes from the welding torch is arbitrarily adjusted.
References Cited (Backward Citations)
AU154636A
Cited
US2241563A
Cited
US3312566A
Cited
US3472995A
Cited
US3549857A
Cited
US3956610A
Cited
US3767890A
Cited
GB1425526A
Cited
US3940586A
Cited
US3989921A
Cited
DE2424666A1
Cited
DE2448620A1
Cited
US4024369A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-01-22 | 1982-07-24 | 1983-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-22 | 1986-07-24 | 1987-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-22 | 1990-07-24 | 1991-01-23 | $7700.00 | Window Closed / Lapsed |