US3631448A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple station intercommunications system
Assignee: HAVALEX Inc
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Filing: 1968-04-26
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Granted: 1971-12-28
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Expires: 1988-04-26
Abstract
Abstract A system interconnecting several stations, each having one of two conditions which it is desired to communicate to all stations so that the conditions of all stations is indicated at each station. A plurality of indicators, one for each station, are at each station, and have an energized and deenergized state for indicating the conditions of the corresponding stations. Silicon controlled rectifiers maintain the energized condition of energized indicators. Each station is sequentially scanned in response to a change in condition of any one of the stations.
Inventors
- 👤 John M Leslie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:31
CPC Classifications
G; G08; G08B; G08B5/00; G08B5/22
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
207 words
A multiple station intercommunications system where each station may be placed either in a first or second condition, each station including visual display means which indicate the conditions of all stations, the improvement comprising: a plurality of visual display means at each of said stations having first and second conditions, each of said display means corresponding to each of said stations, a plurality of bistable means at each of said stations, one corresponding to each of said statiOns and coupled to a corresponding visual display means, each of said bistable means at each of said stations being responsive to the first and second conditions of the corresponding station to permanently place said display means in said first condition if said corresponding station is in said first condition and permanently in said second condition if said corresponding station is in said second condition, each of said stations also including means for sequentially sensing the condition of each of said stations, means for producing a cycle start pulse to initiate said sequential sensing, and means responsive to said cycle start pulse for resetting said plurality of bistable means to a state corresponding to said first condition wherein each station provides a simultaneous display of the condition of all stations.
Claim 2
Dependent Claim
207 words
A multiple station intercommunications system where each station may be placed either in a first or second condition, each station including visual display means which indicate the conditions of all stations, the improvement comprising: a plurality of visual display means at each of said stations having first and second conditions, each of said display means corresponding to each of said stations, a plurality of bistable means at each of said stations, one corresponding to each of said statiOns and coupled to a corresponding visual display means, each of said bistable means at each of said stations being responsive to the first and second conditions of the corresponding station to permanently place said display means in said first condition if said corresponding station is in said first condition and permanently in said second condition if said corresponding station is in said second condition, each of said stations also including means for sequentially sensing the condition of each of said stations, means for producing a cycle start pulse to initiate said sequential sensing, and means responsive to said cycle start pulse for resetting said plurality of bistable means to a state corresponding to said first condition wherein each station provides a simultaneous display of the condition of all stations.
Claim 3
Dependent Claim
31 words
A system as in claim 1 where each station includes means for producing said cycle start pulse in response to such station changing from either of said conditions to the other.
Claim 4
Dependent Claim
15 words
A system as in claim 2 where said start cycle producing means include a capacitor.
Claim 5
Dependent Claim
31 words
A system as in claim 1 where each station is located at a hotel and where said first condition is one of no vacancy and said second condition indicates a vacancy.
Claim 6
Dependent Claim
20 words
A system as in claim 1 where said bistable means are silicon controlled rectifiers having anode, cathode and gate terminals.
Claim 7
Dependent Claim
41 words
A system as in claim 5 where a transistor is coupled to said gate terminal of each rectifier, said transistor normally clamping said gate to ground said transistor being responsive to said second condition of said stations for unclamping said gate.
Claim 8
Dependent Claim
45 words
A system as in claim 1 including internal test means for each station for testing said visual display means, said test means comprising switching means for disconnecting the station under test from all other stations and for concurrently simulating a second condition for all stations.
Claim 9
Dependent Claim
15 words
A system as in claim 1 in which said bistable means are flip flop devices.
Claim 10
Dependent Claim
34 words
A system as in claim 1 where in said first condition a station produces a first signal of a first type and in said second condition produces a second signal of a second type.
Claim 11
Dependent Claim
24 words
A system as in claim 9 in which said first signal is of one frequency and said second signal is of a different frequency.
Claim 12
Dependent Claim
31 words
A system as in claim 9 in which said bistable means are responsive to said first and second signals to switch from one state to the other of said bistable means.
Claim 13
Dependent Claim
21 words
A system as in claim 1 where each station includes means for sequentially sensing the condition of each of said stations.
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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) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |