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US3177291A
Expired / Lapsed
US
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Electronic switching telephone system
Assignee: TDK Micronas GmbH
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Filing: 1961-01-24
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Granted: 1965-04-06
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Expires: 1981-01-24
Abstract
No abstract record available.
Inventors
- 👤 Virgie E Porter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:41
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42; H04Q3/52; H04Q3/521; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/70; H03K17/72; H03K19/00; H03K19/02; H03K19/173; H03K19/177; H03K23/00; H03K23/002; H10; H10B; H10B99/00; H10B99/16; H10B99/20; H10D; H10D99/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
102 words
AN ELECTRIC SWITCHING TELEPHONE SYSTEM COMPRISING A MATRIX INCLUDING A PLURALITY OF FIRST AND SECOND GROUPS OF CONDUCTOR ARRANGED TO PROVIDE INTERSECTING CROSS-POINTS, EACH OF THE GROUPS INCLUDING MESSAGE CARRYING CONDUCTORS AND CONTROL CONDUCTORS, MEANS INCLUDING ELECTRONIC DEVICES AT EACH OF THE CROSSPOINTS FOR EFFECTIVELY COUPLING THE MESSAGE CARRYING CONDUCTORS WHICH INTERSECT THEREAT, MEMORY MEANS INCLUDING A MAGNETIC DEVICE AT EACH OF SAID CROSSPOINTS FOR CONTROLLING SAID ELECTRONIC DEVICES AND FOR TRANSMITTING BUSY SIGNALS WHEN THE CROSSPOINT IS CLOSED, AND MEANS RESPONSIVE TO A COINCIDENCE OF TIME SIGNALS FOR CONTROLLING SAID MAGNETIC AND ELECTRONIC DEVICES IF NO BUSY SIGNALS ARE THEN PRESENT.
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) | 1968-04-05 | 1968-10-05 | 1969-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-04-05 | 1972-10-05 | 1973-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-04-05 | 1976-10-05 | 1977-04-06 | $7700.00 | Window Closed / Lapsed |