Patent US3294928A successfully refreshed from Google Patents.
US3294928A
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Method and apparatus for seam welding of tubes
Assignee: Siemens Schuckertwerke AG
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Filing: 1964-12-30
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Granted: 1966-12-27
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Expires: 1984-12-30
Abstract
No abstract record available.
Inventors
- 👤 Schafer Hans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:12
CPC Classifications
B; B23; B23K; B23K13/00; B23K13/01; B23K13/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
112 words
A METHOD FOR THE SEAM WELDING OF TUBES BY MEANS OF ALTERNATELY CURRENT, COMPRISING THE STEPS OF CONTINUOUSLY FORMING METAL STRIP INTO CYLINDRICAL FORM BY LONGITUDINAL ADVANCEMENT WHILE CONVERGING OPPOSING EDGES OF SUCH STRIP TO A POINT OF MEETING AT A LONGITUDINAL POSITION SUSCEPTIBLE TO VARIANCE DUE TO IRREGULARITIES IN THE SURFACE OF SUCH EDGES, PRODUCING AN ELECTRICALLY CONDUCTING ARC BETWEEN SUCH EDGES BY LOCALIZED DISCHARGE FROM AN ELECTRODE AT A FIXED LONGITUDINAL POSITION IMMEDIATELY BEFORE SAID POINT OF MEETING, AND CAUSING ALTERNATING CURRENT TO FLOW ALONG SUCH EDGES IN ADVANCE OF AND BY WAY OF SAID ELECTRICALLY CONDUCTING ARC TO OBTAIN WELDING OF SAID EDGES TOGETHER AT THEIR POINT OF MEETING.
Claim 2
Independent Claim
112 words
A METHOD FOR THE SEAM WELDING OF TUBES BY MEANS OF ALTERNATELY CURRENT, COMPRISING THE STEPS OF CONTINUOUSLY FORMING METAL STRIP INTO CYLINDRICAL FORM BY LONGITUDINAL ADVANCEMENT WHILE CONVERGING OPPOSING EDGES OF SUCH STRIP TO A POINT OF MEETING AT A LONGITUDINAL POSITION SUSCEPTIBLE TO VARIANCE DUE TO IRREGULARITIES IN THE SURFACE OF SUCH EDGES, PRODUCING AN ELECTRICALLY CONDUCTING ARC BETWEEN SUCH EDGES BY LOCALIZED DISCHARGE FROM AN ELECTRODE AT A FIXED LONGITUDINAL POSITION IMMEDIATELY BEFORE SAID POINT OF MEETING, AND CAUSING ALTERNATING CURRENT TO FLOW ALONG SUCH EDGES IN ADVANCE OF AND BY WAY OF SAID ELECTRICALLY CONDUCTING ARC TO OBTAIN WELDING OF SAID EDGES TOGETHER AT THEIR POINT OF MEETING.
References Cited (Backward Citations)
US2784349A
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US2669639A
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US2800561A
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US2774857A
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US2905805A
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US3146336A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-12-26 | 1970-06-27 | 1970-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-12-26 | 1974-06-27 | 1974-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-12-26 | 1978-06-27 | 1978-12-27 | $7700.00 | Window Closed / Lapsed |