US3637973A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arc welding apparatus
Assignee: Mitsubishi Electric Corp
•
Filing: 1970-02-17
•
Granted: 1972-01-25
•
Expires: 1990-02-17
Abstract
Abstract Upon initiating a welding operation, a relay is operated to connect two electric sources of alternating current in parallel circuit relationship through a contactor to fuse a welding electrode away from a workpiece striking an arc between them. Then another relay is operated to keep one of the sources disabled while the operation proceeds with the other source. Upon short circuiting, the contactor is operated to repeat the above process.
Inventors
- 👤 Jun Ukai
- 👤 Masaki Hiramatu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:46
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/09; B23K9/091; B23K9/10; B23K9/1006
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
137 words
An arc-welding apparatus comprising, in combination, a welding electrode and a workpiece disposed in opposite relationship, a first electric source of alternating current supplying a welding current to both said welding electrode and said workpiece, a second electric source of alternating current connected in parallel circuit relationship with said first electric source, switching means disposed in said parallel circuit formed of said second electric source To open and close said parallel circuit, and control means responsive to short circuiting of said welding electrode and said workpiece to close said switching means to connect said second electric source in parallel relationship to said first electric source, including means responsive to the occurrence of an electric arc across said welding electrode and said workpiece to open said switching means to disconnect said second electric source from said parallel circuit.
Claim 2
Dependent Claim
137 words
An arc-welding apparatus comprising, in combination, a welding electrode and a workpiece disposed in opposite relationship, a first electric source of alternating current supplying a welding current to both said welding electrode and said workpiece, a second electric source of alternating current connected in parallel circuit relationship with said first electric source, switching means disposed in said parallel circuit formed of said second electric source To open and close said parallel circuit, and control means responsive to short circuiting of said welding electrode and said workpiece to close said switching means to connect said second electric source in parallel relationship to said first electric source, including means responsive to the occurrence of an electric arc across said welding electrode and said workpiece to open said switching means to disconnect said second electric source from said parallel circuit.
Claim 3
Dependent Claim
52 words
An arc-welding apparatus as claimed in claim 1 wherein said control means includes a relay operative in response only to a welding voltage appearing across said welding electrode and said workpiece for generating an arc thereacross, and means responsive to the operation of said relay to open and close said switching means.
Claim 4
Dependent Claim
23 words
An arc-welding apparatus as claimed in claim 1 wherein said first and second sources have the drooping characteristics substantially identical to each other.
Claim 5
Dependent Claim
68 words
An arc-welding apparatus as claimed in claim 1 wherein said first and second sources have the drooping characteristics substantially identical to each other and wherein said control means includes a relay operative in response only to a welding voltage appearing across said welding electrode and said workpiece for generating an arc thereacross, and means responsive to the operation of said relay to open and close said switching means.
Claim 6
Dependent Claim
200 words
An arc-welding apparatus comprising, in combination, a welding electrode and a workpiece disposed in opposite relationship, a first electric source of alternating current supplying a welding current to both said welding electrode and said workpiece, a second electric source of alternating current connected in a parallel circuit relationship to said first electric source, switching means disposed in the parallel circuit of said second electric source to open and close said parallel circuit, and control means including first relay means energized in response to the no-load voltage across said first electric source, a second relay means deenergized in response to the energization of said first relay means but energized in response to a welding voltage appearing across said welding electrode and said workpiece upon occurrence of an electric arc thereacross, and an electromagnetic element responsive to the energization of said second relay means to open said switching means to disconnect said second electric source from said first electric source in said parallel circuit during generation of said electric arc, and said second relay means being deenergized in response to short circuiting between the electrode and workpiece for closing said switching means to connect said second electric source in said parallel circuit.
Claim 7
Dependent Claim
200 words
An arc-welding apparatus comprising, in combination, a welding electrode and a workpiece disposed in opposite relationship, a first electric source of alternating current supplying a welding current to both said welding electrode and said workpiece, a second electric source of alternating current connected in a parallel circuit relationship to said first electric source, switching means disposed in the parallel circuit of said second electric source to open and close said parallel circuit, and control means including first relay means energized in response to the no-load voltage across said first electric source, a second relay means deenergized in response to the energization of said first relay means but energized in response to a welding voltage appearing across said welding electrode and said workpiece upon occurrence of an electric arc thereacross, and an electromagnetic element responsive to the energization of said second relay means to open said switching means to disconnect said second electric source from said first electric source in said parallel circuit during generation of said electric arc, and said second relay means being deenergized in response to short circuiting between the electrode and workpiece for closing said switching means to connect said second electric source in said parallel circuit.
References Cited (Backward Citations)
GB784787A
Cited
US2969494A
Cited
US3051828A
Cited
US3249735A
Cited
US3423564A
Cited
US3459920A
Cited
US3502397A
Cited
US3449544A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |