Line lockout circuit
Abstract
Abstract A STATION LINE LOCKOUT CIRCUIT IN A COMMON CONTROL TELEPHONE SYSTEM EMPLOYING A CROSSBAR SWITCHING NETWORK IS DISCLOSED. THE CIRCUIT COMPRISES A SINGLE LOCKOUT RELAY WHICH IS BRIDGED INTO A STATION LINE AND IS AUTOMATICALLY OPERATED BY A COMMON CONTROL CIRCUIT AFTER AN ORIGINATING REGISTER TIMEOUT OCCURS DUE TO A PERMANENT SIGNAL. THE LOCKOUT RELAY COOPERATES WITH THE COMMON CONTROL CIRCUIT TO ACTIVATE A CROSSBAR SWITCH LINE HOLD MAGNET FOR OPENING THE CONVENTIONAL LINE RELAY CIRCUITS TO BLOCK THE INITIATION OF DIAL TONE SERVICE REQUESTS UNTIL AFTER THE PERMANENT SIGNAL IS CLEARED. THE LOCKOUT RELAY LOCKS OPERATED TO THE STATTION LINE, SUPPLIES PERMANENT SIGNAL TONE TO THE LINE, AND MAINTAINS THE HOLD MAGNET ACTIVATED AFTER THE COMMON CONTROL CIRCUITS RELEASE UPON DETERMINING THAT THE LOCKOUT IS EFFECTIVE. D R A W I N G
Inventors
- 👤 Richard Maurice Swanson
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-12-12 | 1976-06-12 | 1976-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-12 | 1980-06-12 | 1980-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-12 | 1984-06-12 | 1984-12-12 | $7700.00 | Window Closed / Lapsed |