Telephone privacy system

• US 4,598,179 A
• Filed: 06/28/1984
• Issued: 07/01/1986
• Est. Priority Date: 06/28/1984
• Status: Expired due to Fees

• Current Assignee: Sakura Telecommunications Incorporated
• Original Assignee: Sakura Telecommunications Incorporated
• Inventors: Emery, Ralph E., Clark, Lloyd E.
• Primary Examiner(s): Dwyer, James L.
• Application Number:
  US06/625,825
• Time in Patent Office: 733 Days
• Field of Search: 179/84 R, 179/84 C, 179/84 SS, 179/84 T, 179/84 VF, 179/5.5, 179/84 A, 179/84 L, 179/2 A, 179/18 BF, 179/99 P, 179/18 FH
• US Class Current: 379/200
• CPC Class Codes: H04M 1/665 by checking the validity of a code
• CPC Class Codes: Y10S 379/911 Distinctive ringing

Abstract

A telephone privacy system provides audible melodies identifying respective authorized callers without requiring the system user to answer the phone. A first ringing signal burst on the user'"'"'s telephone line actuates the telephone ring circuit to announce an incoming call. The second burst places the phone off-hook and returns simulated audible ringing signal to the line so that unauthorized callers are not aware that calls are being screened. The simulated audible ringing signal also serves as an entry request to authorized callers who dial in their identification code after the first burst of simulated audible ringing signal. The entered code activates a tune generator to provide the called party with the caller-identifying melody. A visual indicator is provided to register visible indicia representing authorized calling parties.

Claims

1. A telephone privacy system for use in conjunction with a user'"'"'s telephone line and receiver/transmitter unit for permitting the user to screen incoming calls, without answering the calls, on the basis of a coded identification signal transmitted by a calling party on the telephone line, said system comprising:

first means responsive to said coded identification signal received on the user'"'"'s telephone line for automatically providing a plurality of audio tones in a sequence which is determined by the receive coded identification signal; and

second means for rendering said plurality of audio tones audible externally of said system;

wherein plural different coded identification signals can be employed in said system to uniquely identify respective authorized callers, and wherein said first means comprises;

decoder means responsive to received coded identification signals for providing respective decoded address signals representing the coded identification in the received signal; and

tune generator means for providing said plurality of tones as a recognizable tune determined by the decoded address signal.

2. The system according to claim 1 further comprising visual display means responsive to said decoded address signals for visually displaying an indication of the identify of the caller represented by the received coded identification signals.

3. The system according to claim 1 further comprising:

ringing signal detection means responsive to sequential bursts of ringing signal appearing on the user'"'"'s telephone line for permitting actuation of a ringing circuit in the user'"'"'s unit in response to at least one of said bursts, and for placing the user'"'"'s line in an off-hook state in response to a subsequent burst.

4. The system according to claim 3 further comprising means responsive to said off-hook state for transmitting simulated audible ringing signal on said user'"'"'s line to the calling party.

5. The system according to claim 3 further comprising means responsive to said off-hook state for transmitting an entry request signal on the user'"'"'s line to indicate to the calling party that a coded identification signal can be received and processed by said system.

6. The system according to claim 5 wherein said entry request signal is a simulated audible ringing signal.

7. The system according to claim 6 wherein said entry request signal is a sequence of bursts of an audible signal.

8. The system according to claim 1 further comprising switch means for selectively disconnecting said system from the user'"'"'s telephone line.

9. A telephone privacy system for use with a user'"'"'s telephone set connected to the user'"'"'s telephone line, said system comprising:

ringing signal detection means responsive to plural sequential bursts of ringing signal appearing on the user'"'"'s line for permitting actuation of a ringing circuit in the user'"'"'s telephone set in response to at least one of said bursts and for placing the user'"'"'s line in an off-hook status in response to a subsequent burst;

means responsive to said off-hook state for transmitting a simulated audible ringing signal on the user'"'"'s line; and

means operative in the off-hook state for decoding caller-identifying coded signals appearing on the user'"'"'s line.

10. The system according to claim 9 wherein said means for transmitting transmits said simulated audible ringing signal as a sequence of bursts of an audible signal.

11. The system according to claim 9 wherein said means for decoding comprises means for providing melodies as audible tone sequences in response to respective caller-identifying coded signals received on the user'"'"'s line.

12. The system according to claim 9 wherein said means for decoding comprises:

decoder means responsive to each received caller-identifying coded signal for providing respective decoded address signals representing the identified caller; and

tune generator means for providing a plurality of audio tones as said melodies, each melody being provided in accordance with the particular decoded address signals.

13. The system according to claim 12 further comprising visual display means responsive to said decoded address signals for visually displaying an indication of the identity of the caller represented by the received coded identification signals.

14. A telephone privacy system for a telephone set user to identify and distinguish between authorized calling parties for calls received on the user'"'"'s telephone line, said system comprising:

ringing signal detection means responsive to plural sequential bursts of ringlng signal appearing on the user'"'"'s line for permitting actuation of a ringing circuit in the user'"'"'s telephone set in response to at least one of said bursts, and for placing the user'"'"'s line in an off-hook status in response to a subsequent burst;

entry request means responsive to said off-hook status for transmitting an entry request signal on the user'"'"'s line to indicate to a calling party that a coded identification signal can be received and processed by said system;

means operative in the off-hook state for decoding caller-identifying coded signals appearing on the user'"'"'s line; and

indicator means responsive to said means for decoding for providing a humanly perceptible indication identifying an authorized calling party whose coded identification signal has been received on the user'"'"'s line.

15. The system according to claim 14 wherein said indicator means comprises means for providing respective audible melodies representing each authorized caller whose coded identification signal has been received on the user'"'"'s line, and for providing a further melody in response to failure to receive an authorized caller'"'"'s coded identification signal within a predetermined time after said entry request signal has been transmitted on the user'"'"'s line.

16. The system according to claim 15 wherein said entry request signal is a simulated audible ringing signal.

17. The system according to claim 16 further comprising means responsive to said means for decoding for visually displaying symbols identifying authorized callers whose coded identification signals have been received on the user'"'"'s line.

18. The system according to claim 14 wherein said indicator means comprises means responsive to said means for decoding for visually displaying symbols identifying authorized callers whose coded identification signals have been received on the user'"'"'s line.

19. The system according to claim 14 wherein said means for decoding comprises:

decoder means responsive to each received caller-identifying coded signal for providing respective decoded address signals representing the identified caller; and

tune generator means for providing a plurality of audio tones as said melodies, each melody being provided in accordance with the particular decoded address signals.