US3692973A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arc welding
Assignee: Panasonic Holdings Corp
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Filing: 1970-09-01
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Granted: 1972-09-19
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Expires: 1990-09-01
Abstract
Abstract According to the invention, there is provided a method for arc welding, wherein a plasma arch having a high arc energy density may be obtained without using any solid member directly restraining the flaring of the arc but by effectively utilizing two or more concentric gas streams ejected from the torch nozzle for focusing the arc.
Inventors
- 👤 Takeshi Oku
- 👤 Kazushige Hirasawa
- 👤 Yoshimitsu Matsumoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:43
CPC Classifications
H; H05; H05H; H05H1/00; H05H1/24; H05H1/26; H05H1/32; H05H1/34; H05H1/341; B; B23; B23K; B23K10/00; B23K10/02; H05H1/3405
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
229 words
A method of welding base metals comprising the steps of producing an electric arc between said base metal and an electrode facing said base metal, flowing a first gas stream comprising a gas in which an electric plasma arc is producible by a relatively low energy, in a direction toward said base metal to surround and in cOntact with at least the part of said electrode closest to said base metal and to surround said electric arc, and producing a plasma arc in said first gas stream, said first gas stream having a sufficiently small transverse cross-sectional area and velocity so that it does not dig and spatter the molten portion of said base metal when said plasma arc is produced therein, and flowing a second gas stream comprising a gas in which an electric plasma arc is producible by a larger energy than the plasma arcing energy of the gas of said first gas stream, said second gas stream flowing in the same direction as said first gas stream and surrounding said first gas stream, said second gas stream also constricting the electric arc within the flow of said first gas stream, thereby converting the electric arc to an electric plasma arc and constricting the plasma arc in a desired range without any solid mechanical constricting member closer to the base metal than the tip of said electrode.
Claim 2
Independent Claim
229 words
A method of welding base metals comprising the steps of producing an electric arc between said base metal and an electrode facing said base metal, flowing a first gas stream comprising a gas in which an electric plasma arc is producible by a relatively low energy, in a direction toward said base metal to surround and in cOntact with at least the part of said electrode closest to said base metal and to surround said electric arc, and producing a plasma arc in said first gas stream, said first gas stream having a sufficiently small transverse cross-sectional area and velocity so that it does not dig and spatter the molten portion of said base metal when said plasma arc is produced therein, and flowing a second gas stream comprising a gas in which an electric plasma arc is producible by a larger energy than the plasma arcing energy of the gas of said first gas stream, said second gas stream flowing in the same direction as said first gas stream and surrounding said first gas stream, said second gas stream also constricting the electric arc within the flow of said first gas stream, thereby converting the electric arc to an electric plasma arc and constricting the plasma arc in a desired range without any solid mechanical constricting member closer to the base metal than the tip of said electrode.
Claim 3
Dependent Claim
41 words
The method of welding base metals according to claim 1, wherein the gas comprising said second gas stream has a cooling capacity for the plasma arc which is larger than the cooling capacity of the gas comprising said first gas stream.
Claim 4
Dependent Claim
26 words
The method of welding base metals according to claim 1, wherein said second gas stream has a higher velocity than that of said first gas stream.
Claim 5
Dependent Claim
30 words
The method of welding base metals according to claim 2, wherein the gas comprising said second gas stream has a higher velocity than the velocity of said first gas stream.
Claim 6
Dependent Claim
24 words
The method of welding base metals according to claim 1, wherein said first gas stream comprises argon, and said second gas stream comprises CO2.
Claim 7
Independent Claim
201 words
A method of welding base metals comprising the steps of providing an electric plasma arc between a base metal and an electrode facing said base metal, flowing a first gas stream in a direction toward said base metal and surrounding and in contact with at least the part of said electrode closest to said base metal and surrounding said electric arc and producing a plasma arc in said first gas stream, said first gas stream having a sufficiently small transverse cross-sectional area and velocity so that it does not dig and spatter the molten portion of said base metal when said plasma arc is produced therein, and flowing a second gas stream in the same direction as said first gas stream and surrounding said first gas stream, the gas of said second gas stream having a cooling capacity for the plasma arc greater than the cooling capacity of said first gas stream, said second gas stream flowing at a sufficient velocity to constrict the plasma arc within the flow of said first gas stream, whereby said plasma arc is constricted in a desired range without any solid mechanical constricting member closer to the base metal than the tip of said electrode.
Claim 8
Independent Claim
201 words
A method of welding base metals comprising the steps of providing an electric plasma arc between a base metal and an electrode facing said base metal, flowing a first gas stream in a direction toward said base metal and surrounding and in contact with at least the part of said electrode closest to said base metal and surrounding said electric arc and producing a plasma arc in said first gas stream, said first gas stream having a sufficiently small transverse cross-sectional area and velocity so that it does not dig and spatter the molten portion of said base metal when said plasma arc is produced therein, and flowing a second gas stream in the same direction as said first gas stream and surrounding said first gas stream, the gas of said second gas stream having a cooling capacity for the plasma arc greater than the cooling capacity of said first gas stream, said second gas stream flowing at a sufficient velocity to constrict the plasma arc within the flow of said first gas stream, whereby said plasma arc is constricted in a desired range without any solid mechanical constricting member closer to the base metal than the tip of said electrode.
Claim 9
Dependent Claim
26 words
The method of welding base metals according to claim 6, wherein said second gas stream has a velocity higher than that of said first gas stream.
Claim 10
Dependent Claim
50 words
The method of welding base metals according to claim 1, further comprising the step of flowing a third gas stream in the same direction of said second gas stream so that said electrode, said plasma arc, and the molten portion of said base metal are protected from the ambient atmosphere.
Claim 11
Dependent Claim
50 words
The method of welding base metals according to claim 2, further comprising the step of flowing a third gas stream in the same direction of said second gas stream so that said electrode, said plasma arc, and the molten portion of said base metal are protected from the ambient atmosphere.
Claim 12
Dependent Claim
50 words
The method of welding base metals according to claim 3, further comprising the step of flowing a third gas stream in the same direction of said second gas stream so that said electrode, said plasma arc, and the molten portion of said base metal are protected from the ambient atmosphere.
Claim 13
Dependent Claim
50 words
The method of welding base metals according to claim 5, further comprising the step of flowing a third gas stream in the same dirEction of said second gas stream so that said electrode, said plasma arc, and the molten portion of said base metal are protected from the ambient atmosphere.
Claim 14
Dependent Claim
50 words
The method of welding base metals according to claim 6, further comprising the step of flowing a third gas stream in the same direction of said second gas stream so that said electrode, said plasma arc, and the molten portion of said base metal are protected from the ambient atmosphere.
Claim 15
Dependent Claim
50 words
The method of welding base metals according to claim 7, further comprising the step of flowing a third gas stream in the same direction of said second gas stream so that said electrode, said plasma arc, and the molten portion of said base metal are protected from the ambient atmosphere.
Claim 16
Dependent Claim
26 words
The method of welding base metals according to claim 8, wherein said first and third gas streams comprise argon, and said second gas stream comprises CO2.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |