Telephone privacy device

• US 5,231,658 A
• Filed: 02/25/1992
• Issued: 07/27/1993
• Est. Priority Date: 02/25/1992
• Status: Expired due to Fees

• Current Assignee: Vakis Eftechiou
• Original Assignee: Vakis Eftechiou
• Inventors: Eftechiou, Vakis
• Primary Examiner(s): Schreyer, Stafford
• Application Number:
  US07/841,118
• Time in Patent Office: 518 Days
• Field of Search: 379/184, 379/168, 379/194, 379/195, 379/199, 379/442
• US Class Current: 379/194
• CPC Class Codes: H04M 1/70 Lock-out or secrecy arrangements in party-line systems
• CPC Class Codes: H04M 3/16 with lock-out or secrecy provision in party-line systems
• CPC Class Codes: H04M 9/02 involving a common line for all parties

Abstract

A telephone privacy protector for connection to a common exchange line and each one of at least two telephone operated devices sharing a line includes a voice connecting circuit for connection between a respective telephone line operated device and the line. There is a control deice connected to the circuit having an on and off state wherein the control device in the on state permits the voice connecting circuit to operate. There are means for turing the control device on when the respective telephone line operated device goes off hook provided that no other telephone line operated device sharing the line is off hook. There are means for providing a residual charge to the control device in order to reactivate same after the respective telephone line operated device is placed momentarily on hook and then returned to an off hook state while any other telephone line operated device connected to the line is off hook.

Claims

1. A telephone privacy protector for connection to common exchange line and one of at least two telephone line operated devices sharing said line, the privacy protector comprising:

a voice connecting circuit for connection between a respective telephone line operated device and the line;

a silicon controlled rectifier connected to said circuit having an on and off state;

means for turning said rectifier on when said respective telephone line operated device goes off hook, provided no other telephone line operated device connected to the line is off hook, thereby permitting said voice connecting circuit to operate; and

means for providing a residual charge to said rectifier in order to reactivate same after said respective telephone line operated device is placed momentarily on hook and then returned to an off hook state while any other telephone line operated device connected to said line is off hook.

2. A telephone privacy protector according to claim 1 wherein said means to turn said rectifier on is a zener diode electrically connected to a gate of said silicon controlled rectifier.

3. A telephone privacy protector according to claim 2 wherein said means for providing a residual charge comprises a resistor and a timing circuit both electrically connected to said silicon controlled rectifier.

4. A telephone privacy protector according to claim 3 wherein said timing circuit comprises a capacitor electrically connected to a resistor.

5. A telephone privacy protector according to claim 2, wherein said voice connecting circuit comprises a rectifier bridge having two opposite pairs of rectifier junctions, one pair of said junctions adapted for connection between said exchange line an said respective telephone line operated device and the other pair of junctions being connected to said silicon controlled rectifier.

6. A telephone privacy protector for connection to a common exchange line and one of at least two telephone line operated devices sharing the line, the privacy protector comprising:

a voice connecting circuit for connection between a respective telephone line operated device and the line;

a control device connected to said circuit having an on and off state, said device in said on state permitting said voice connecting circuit to operate;

means for turning said control device on when said one telephone line operated device goes off hook provided that no other telephone line operated device sharing the line is off hook; and

means for providing a residual charge to said control device in order to reactivate same after said one telephone line operated device is placed momentarily on hook and then returned to an off hook state While any other telephone line operated device connected to said line is off hook.

7. A telephone privacy protector according to claim 6 wherein said means for turning said control device on is a zener diode electrically connected to said control device.

8. A telephone privacy protector device according to claim 6 wherein said means for providing a residual charge comprises a resistor and a timing circuit both electrically connected to said control device.

9. A telephone privacy protector device according to claim 8 Wherein said timing circuit comprises a capacitor electrically connected to a resistor.

10. A telephone privacy device according to claim 8 wherein said voice connecting circuit comprises a rectifier bridge having two opposite pairs of rectifier junctions, one pair of said junctions adapted for connection between said exchange line and said respective telephone line operated device and the other pair of junctions being connected to said control device.

11. A privacy protecting jack for connection to a common exchange line and one of at least two telephone line operated devices sharing the line, the jack comprising:

a jack body having one end adapted for insertion in a connecting jack operatively connected to said exchange line and having a first jack receiving socket;

a voice connecting circuit for connection between said one telephone line operated device and the line;

a control device connected to said circuit having an on and off state, said device in said on state permitting said voice connecting circuit to operate,

means for turning said control device on when said one telephone line operated device goes off hook provided that no other telephone line operated device sharing the line is off hook;

means for providing a residual charge to said control device in order to reactivate same after said one telephone line operated device is placed momentarily on hook and then returned to an off hook state while any other telephone line operated device connected to said line is off hook,

wherein said connecting circuit, control device, turning on means, and said residual charge providing means are mounted in said jack body.

12. A jack according to claim 11 wherein said jack body has a second jack receiving socket thereby allowing two telephone line operated devices to be connected to the same jack.

13. A jack according to claim 11 wherein said control device is a silicon controlled rectifier.

14. A jack according to claim 11 wherein said means for turning said control device on is a zener diode electrically connected to said control device.

15. A telephone privacy protector device according to claim 11 wherein said means for providing a residual charge comprises a resistor and a timing circuit both electrically connected to said control device.

16. A telephone privacy protector device according to claim 15 wherein said timing circuit comprises a capacitor electrically connected to resistor.