US4638124A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Key telephone system with distributed control
Assignee: U S Holding Co Inc
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Filing: 1984-09-21
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Granted: 1987-01-20
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Expires: 2004-09-21
Abstract
Abstract A system is presented for accessing a plurality of central office lines, PBX, etc. by a plurality of stations and for exchanging signals between the stations. Each station is provided with a self-sufficient microprocessor which controls all the functions of the station. The microprocessors exchange control signals to indicate the status of each station and each line. A common intercom line is provided for both audio signals and control signals. Each station is assigned a unique address so that each station is able to dial up another station for intercom communication by generating the proper control signals. Each station is also provided with a switch matrix for selectively accessing any of the lines, line status indicating means, and line holding means which is automatically released when any station accesses the held line.
Inventors
- 👤 Franklin Hargrave
- 👤 Francisco A. Middleton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:23
CPC Classifications
H; H04; H04M; H04M9/00; H04M9/002; H04M9/005
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
126 words
A communication system, comprising: an intercom line; a plurality of stations, each station connected to said intercom line and a plurality of telephone lines, said stations each including, means for transmitting and receiving information, switch means for selectively accessing said transmitting and receiving means to one of said telephone lines and intercom line, and control means for generating and receiving control signals and for controlling said switch means, said control means of each station being adapted to generate binary control signals, and each station further comprises means for converting said binary signals to PCM control signals; and means for exchanging said control signals between stations, whereby the system is distributively controlled by said control means in each station and there is no need for centralized control.
Claim 2
Dependent Claim
126 words
A communication system, comprising: an intercom line; a plurality of stations, each station connected to said intercom line and a plurality of telephone lines, said stations each including, means for transmitting and receiving information, switch means for selectively accessing said transmitting and receiving means to one of said telephone lines and intercom line, and control means for generating and receiving control signals and for controlling said switch means, said control means of each station being adapted to generate binary control signals, and each station further comprises means for converting said binary signals to PCM control signals; and means for exchanging said control signals between stations, whereby the system is distributively controlled by said control means in each station and there is no need for centralized control.
Claim 3
Dependent Claim
16 words
The system of claim 1 further comprising indicating means for indicating the status of each line.
Claim 4
Dependent Claim
17 words
The station of claim 1 wherein said PCM control signals have a range outside the audio range.
Claim 5
Dependent Claim
26 words
The system of claim 1 wherein said means for exchanging said control signals between stations includes means for transmitting said control signals over said intercom line.
Claim 6
Dependent Claim
25 words
The system of claim 4 wherein said control signals are transmitted to all other stations and each station functions as required by the control signals.
Claim 7
Dependent Claim
25 words
The system of claim 1 wherein said control signals are exchanged with all other stations, each station functioning in response to the received control signals.
Claim 8
Dependent Claim
17 words
The system of claim 1 wherein said means for transmitting and receiving information comprises a telephone subset.
Claim 9
Dependent Claim
43 words
The system of claim 7 wherein each station is assigned a unique address and wherein said control means is adapted to call up a preselected station for intercom communication by generating an intercom control signal corresponding to the address of the selected station.
Claim 10
Dependent Claim
37 words
The system of claim 8 wherein the control means is adapted to receive intercom control signals and to recognize the intercom control signal corresponding to the unique address of the station of which it is a part.
Claim 11
Dependent Claim
39 words
The system of claim 9 wherein each station comprises ringing means and said control means is adapted to access said telephone subset to said intercom line when the intercom control signal corresponding to the respective station address is received.
Claim 12
Dependent Claim
30 words
The system of claim 1 wherein each station further comprises paging means controlled by said control means, said paging means being adapted to reproduce paging signals generated by a station.
Claim 13
Dependent Claim
51 words
The system of claim 7 wherein each station comprises sensing means for sensing a ringing signal on a telephone line said sensing means being operatively connected to said control means, said control means being adapted to selectively access the subset to the telephone line on which the ringing signal was received.
Claim 14
Dependent Claim
15 words
The system of claim 1 wherein the information transmitted and received is an audio range.
Claim 15
Dependent Claim
75 words
A station for selectively exchanging signals on several telephone lines and an intercom line, comprising: a telephone subset; a microprocessor; switch means for selectively accessing said telephone subset to said telephone and intercom lines, said switch means being activated by said microprocessor; and control means operatively connected to said switch means and said microprocessor for selectively controlling said switch means, said microprocessor generating BCD signals and said control means comprises a BCD to decimal decoder.
Claim 16
Dependent Claim
75 words
A station for selectively exchanging signals on several telephone lines and an intercom line, comprising: a telephone subset; a microprocessor; switch means for selectively accessing said telephone subset to said telephone and intercom lines, said switch means being activated by said microprocessor; and control means operatively connected to said switch means and said microprocessor for selectively controlling said switch means, said microprocessor generating BCD signals and said control means comprises a BCD to decimal decoder.
Claim 17
Dependent Claim
34 words
The station of claim 14 wherein said subset comprises a dial means for generating dialing signals, a dial means activating means, and a handset for reproducing signals from and generating signals for said lines.
Claim 18
Dependent Claim
43 words
The station of claim 14 further comprising ring sensing means operatively connected between said lines and said microprocessor for sensing ringing signals and a means which is activated by said microprocessor in response to said ringing signals for producing an audio ringing signal.
Claim 19
Dependent Claim
14 words
The station of claim 16 wherein said ring sensing means comprise optical isolator means.
Claim 20
Dependent Claim
26 words
The station of claim 14 further comprising visual line status indicating means operatively connected to said microprocessor to indicate the presence of activity on said lines.
Claim 21
Dependent Claim
26 words
The station of claim 18 herein said line status indicator means comprises a plurality of light emitting devices, each device corresponding to one of the lines.
Claim 22
Dependent Claim
26 words
The station of claim 19 wherein said microprocessor is adapted to activate intermittently the corresponding indicator means, when a ringing signal is received on a line.
Claim 23
Dependent Claim
26 words
The station of claim 19 wherein said microprocessor is adapted to activate continuously the corresponding indicator device when said subset accesses one of the said lines.
Claim 24
Dependent Claim
26 words
The station of claim 14 wherein said microprocessor is adapted to release said holding means when the respective held line has been accessed by any station.
Claim 25
Dependent Claim
13 words
The station of claim 22 wherein said holding means comprises optical isolator means.
Claim 26
Dependent Claim
28 words
The station of claim 14 wherein said switch means are arranged to connect said subset to a preselected telephone line in case of power failure to said station.
Claim 27
Dependent Claim
32 words
The station of claim 14 further comprising means for requesting access to one of said telephone and intercom lines operatively connected to said microprocessor to connect the subset to the corresponding line.
Claim 28
Dependent Claim
17 words
The station of claim 15 further comprising means for detecting intercom dial pulses generated by said subset.
Claim 29
Dependent Claim
22 words
The station of claim 26 wherein the microprocessor is adapted to produce intercom dial control signals corresponding to said intercom dial pulses.
Claim 30
Dependent Claim
17 words
The station of claim 16, wherein the ring sensing means galvanically isolates the microprocessor from said lines.
Claim 31
Dependent Claim
23 words
The station of claim 19, wherein the microprocessor is adapted to activate the corresponding indicator device when a line is placed on hold.
Claim 32
Dependent Claim
25 words
The station of claim 19, wherein the microprocessor is adapted to activate the corresponding indicator device when a line is being accessed by the station.
Claim 33
Dependent Claim
16 words
The station of claim 14, wherein the holding means galvanically isolates the microprocessor from said lines.
Claim 34
Dependent Claim
99 words
A station for selectively exchanging signals on several telephone lines and an intercom line, comprising: a telephone subset; a microprocessor; switch means for selectively accessing said telephone subset to said telephone and intercom lines, said switch means being activated by said microprocessor; means for exchanging intercom control signals on said intercom line; and station identification means, said station identification means being uniquely preselectable, and said microprocessor being adapted to recognize received intercom control means corresponding to said station identification said station further comprising announcing means operatively connected to said microprocessor to indicate when intercom control signal has been recognized.
Claim 35
Dependent Claim
99 words
A station for selectively exchanging signals on several telephone lines and an intercom line, comprising: a telephone subset; a microprocessor; switch means for selectively accessing said telephone subset to said telephone and intercom lines, said switch means being activated by said microprocessor; means for exchanging intercom control signals on said intercom line; and station identification means, said station identification means being uniquely preselectable, and said microprocessor being adapted to recognize received intercom control means corresponding to said station identification said station further comprising announcing means operatively connected to said microprocessor to indicate when intercom control signal has been recognized.
Claim 36
Dependent Claim
12 words
The station of claim 32 wherein said announcing means comprises a speaker.
Claim 37
Dependent Claim
15 words
The station of claim 32 wherein said microprocessor is adapted to detect control signal collisions.
Claim 38
Dependent Claim
21 words
The station of claim 34 wherein said microprocessor is adapted to detect control signal collisions by comparing outgoing and incoming signals.
Claim 39
Dependent Claim
22 words
The station of claim 34 wherein the microprocessor is adapted to repeat outgoing control signals when a control signal collision is detected.
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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) | 1990-01-19 | 1990-07-21 | 1991-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-19 | 1994-07-21 | 1995-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-19 | 1998-07-21 | 1999-01-20 | $7700.00 | Window Closed / Lapsed |