US4618760A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shielded arc welding using auxiliary voltage
Assignee: Welding Institute England
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Filing: 1985-01-08
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Granted: 1986-10-21
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Expires: 2005-01-08
Abstract
Abstract Shielded arc welding apparatus advances a consumable electrode towards a workpiece; applies a welding voltage between the electrode and the workpiece; and applies an auxiliary voltage between the electrode and the workpiece, whereby the auxiliary voltage initiates an arc between the electrode and the workpiece before the electrode engages the workpiece.
Inventors
- 👤 Michael G. Murch
- 👤 Geoffrey B. Melton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:10
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/06; B23K9/067; B23K9/0672; B23K9/0678
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
68 words
A method of shielded arc welding using a consumable electrode, said method comprising applying a welding voltage between said electrode and a workpiece; applying an auxiliary substantially constant unipolar voltage between said electrode and said workpiece; and advancing said electrode towards said workpiece, while said auxiliary voltage is applied, whereby said auxiliary voltage initiates an arc between said electrode and said workpiece before said electrode engages said workpiece.
Claim 2
Independent Claim
68 words
A method of shielded arc welding using a consumable electrode, said method comprising applying a welding voltage between said electrode and a workpiece; applying an auxiliary substantially constant unipolar voltage between said electrode and said workpiece; and advancing said electrode towards said workpiece, while said auxiliary voltage is applied, whereby said auxiliary voltage initiates an arc between said electrode and said workpiece before said electrode engages said workpiece.
Claim 3
Dependent Claim
22 words
A method according to claim 1, wherein said step of advancing said electrode commences shortly after said auxiliary voltage has been applied.
Claim 4
Dependent Claim
19 words
A method according to claim 1, wherein said electrode is advanced at a speed in the range 20-100 mm/sec.
Claim 5
Dependent Claim
16 words
A method according to claim 1, wherein said auxiliary voltage lies in the range 400-1000 V.
Claim 6
Dependent Claim
16 words
A method according to claim 4, wherein said auxiliary voltage lies in the range 600-750 V.
Claim 7
Dependent Claim
20 words
A method according to claim 1, wherein said auxiliary voltage is applied in the form of a low frequency surge.
Claim 8
Independent Claim
94 words
A method of shielded arc welding using a consumable electrode, said method comprising applying a welding voltage between said electrode and a workpiece; applying an auxiliary, unipolar voltage between said electrode and said workpiece; and advancing said electrode towards said workpiece while said auxiliary voltage is applied, wherein said magnitude of said auxiliary voltage generally increases from an initial value to a value at which an arc is initiated between said electrode and said workpiece, whereby said auxiliary voltage initiates said arc between said electrode and said workpiece before said electrode engages said workpiece.
Claim 9
Independent Claim
94 words
A method of shielded arc welding using a consumable electrode, said method comprising applying a welding voltage between said electrode and a workpiece; applying an auxiliary, unipolar voltage between said electrode and said workpiece; and advancing said electrode towards said workpiece while said auxiliary voltage is applied, wherein said magnitude of said auxiliary voltage generally increases from an initial value to a value at which an arc is initiated between said electrode and said workpiece, whereby said auxiliary voltage initiates said arc between said electrode and said workpiece before said electrode engages said workpiece.
Claim 10
Dependent Claim
34 words
A method according to claim 7, wherein said rate of increase in said magnitude of said auxiliary voltage lies in the range of 1 kV in 0.1 seconds to 1 kV in 0.01 seconds.
Claim 11
Dependent Claim
15 words
A method according to claim 8, wherein said magnitude of said auxiliary voltage increases exponentially.
Claim 12
Dependent Claim
15 words
A method according to claim 7, wherein said magnitude of said auxiliary voltage increases exponentially.
Claim 13
Dependent Claim
22 words
A method according to claim 7, wherein said step of advancing said electrode commences shortly after said auxiliary voltage has been applied.
Claim 14
Dependent Claim
19 words
A method according to claim 7, wherein said electrode is advanced at a speed in the range 20-100 mm/sec.
Claim 15
Dependent Claim
16 words
A method according to claim 7, wherein said auxiliary voltage lies in the range 400-1000 V.
Claim 16
Dependent Claim
16 words
A method according to claim 13, wherein said auxiliary voltage lies in the range 600-750 V.
Claim 17
Dependent Claim
96 words
Shielded arc welding apparatus comprising means for advancing a consumable electrode towards a workpiece; means for applying a welding voltage between said electrode and said workpiece; and auxiliary voltage supply means for applying an auxiliary unipolar voltage between said electrode and said workpiece, said auxiliary voltage supply means being adapted to supply an auxiliary voltage which generally increases from an initial value to a value at which an arc is initiated between said electrode and said workpiece, whereby said auxiliary voltage initiates an arc between said electrode and said workpiece before said electrode engages said workpiece.
Claim 18
Dependent Claim
96 words
Shielded arc welding apparatus comprising means for advancing a consumable electrode towards a workpiece; means for applying a welding voltage between said electrode and said workpiece; and auxiliary voltage supply means for applying an auxiliary unipolar voltage between said electrode and said workpiece, said auxiliary voltage supply means being adapted to supply an auxiliary voltage which generally increases from an initial value to a value at which an arc is initiated between said electrode and said workpiece, whereby said auxiliary voltage initiates an arc between said electrode and said workpiece before said electrode engages said workpiece.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1989-10-20 | 1990-04-21 | 1990-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-20 | 1994-04-21 | 1994-10-21 | $3760.00 | Window Closed / Lapsed |
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