Patent US3725595A successfully refreshed from Google Patents.
US3725595A
Expired / Lapsed
US
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Electronic conversion and secrecy apparatus
Assignee: Individual
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Filing: 1971-03-02
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Granted: 1973-04-03
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Expires: 1991-03-02
Abstract
Abstract An apparatus is disclosed which is inserted into a telephone party line to convert such party line into a private line in response to a telephone call involving a party in the party line and provide secrecy to such call and prevent interference and eavesdropping with a completed call by other parties in the party line.
Inventors
- 👤 B Esfahani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:25
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/68; H04M1/70
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
163 words
An apparatus for converting telephone party line service into exclusive line service by connecting the telephone of a predetermined party to an incoming call for such party and excluding other parties of the party line from such call, comprising: a. selection means responsive to a selection signal in the incoming call for connecting the incoming call to the telephone of a predetermined call party; b. tone generator means for signalling the telephone of the predetermined party of the presence of the incoming call; c. privacy means for excluding the other parties of the party line from the call to the predetermined party, wherein telephone calls to predetermined called parties of the party line service are protected from interference by other parties; and d. monitor means for receiving a test signal from the telephone exchange, said monitor means returning the apparatus to a party line arrangement in response to said test signal whereby the apparatus is compatible with testing equipment in the telephone exchange.
Claim 2
Independent Claim
163 words
An apparatus for converting telephone party line service into exclusive line service by connecting the telephone of a predetermined party to an incoming call for such party and excluding other parties of the party line from such call, comprising: a. selection means responsive to a selection signal in the incoming call for connecting the incoming call to the telephone of a predetermined call party; b. tone generator means for signalling the telephone of the predetermined party of the presence of the incoming call; c. privacy means for excluding the other parties of the party line from the call to the predetermined party, wherein telephone calls to predetermined called parties of the party line service are protected from interference by other parties; and d. monitor means for receiving a test signal from the telephone exchange, said monitor means returning the apparatus to a party line arrangement in response to said test signal whereby the apparatus is compatible with testing equipment in the telephone exchange.
Claim 3
Dependent Claim
19 words
The structure of claim 1 further including control means responsive to an incoming ringing signal for activating the apparatus.
Claim 4
Dependent Claim
39 words
The structure of claim 2, wherein said control means comprises: means for connecting the output of said tone generator means to the incoming call wherein the calling party may hear the signals to the telephone of the called party.
Claim 5
Dependent Claim
30 words
The structure of claim 2, wherein said control means comprises: means for providing a return current after receipt of the incoming call to control switching eqUipment at the telephone exchange.
Claim 6
Dependent Claim
32 words
The structure of claim 1, wherein said selection means comprises: means for reshaping the pulses of the selection signal, whereupon the apparatus is protected from noise and static present on telephone lines.
Claim 7
Dependent Claim
45 words
The structure of claim 1, wherein said privacy means comprises: means for preventing the telephones of other parties from receiving the signal from said tone generator means, wherein only the telephone of the called party receives the signal of the presence of an incoming call.
Claim 8
Dependent Claim
41 words
The structure of claim 1, wherein said privacy means comprises: means for providing a busy signal to other parties during a call to the predetermined party wherein other parties are notified that a call is in progress on the party line.
Claim 9
Dependent Claim
36 words
The structure of claim 1, further including: a. power supply means for energizing the apparatus; and b. means for returning the telephones to party line service in response to a failure of said power supply means.
Claim 10
Dependent Claim
34 words
The structure of claim 1 wherein said selection means comprises: primary means responsive to the absence of a selection signal for connecting the incoming call to a primary preselected party on the party line.
Claim 11
Dependent Claim
33 words
The structure of claim 9 wherein said selection means comprises: time control means for controlling the duration of time for reception of the selection signal, said time control means energizing said primary means.
Claim 12
Dependent Claim
140 words
A telephone secrecy apparatus preventing eavesdropping with a telephone call to a predetermined called party, comprising: a. selection means responsive to a selection signal in the incoming call for connecting the incoming call to the telephone of a predetermined called party; b. tone generator means for signalling the telephone of the predetermined party of the presence of the incoming call; c. privacy means for excluding the other parties of the party line from the call to the predetermined party, wherein telephone calls to predetermined called parties of the party line service are protected from eavesdropping by other parties; and d. monitor means for receiving a test signal from the telephone exchange, said monitor means returning the apparatus to a party line arrangement in response to said test signal whereby the apparatus is compatible with testing equipment in the telephone exchange.
Claim 13
Dependent Claim
140 words
A telephone secrecy apparatus preventing eavesdropping with a telephone call to a predetermined called party, comprising: a. selection means responsive to a selection signal in the incoming call for connecting the incoming call to the telephone of a predetermined called party; b. tone generator means for signalling the telephone of the predetermined party of the presence of the incoming call; c. privacy means for excluding the other parties of the party line from the call to the predetermined party, wherein telephone calls to predetermined called parties of the party line service are protected from eavesdropping by other parties; and d. monitor means for receiving a test signal from the telephone exchange, said monitor means returning the apparatus to a party line arrangement in response to said test signal whereby the apparatus is compatible with testing equipment in the telephone exchange.
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |