
US Patent No: 4,825,460
Number of patents in Portfolio can not be more than 2000
Line interface unit for caller-controlled receipt and delivery of voice messages
Stats
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Apr 25, 1989
Issued date -
Jun 22, 1988
filing date -
07/209,891
serial no -
Expired
status
Importance
Abstract
A line interface unit for controlling receipt and delivery of voice messages over a telephone system having a voice message facility connectable to at least one calling station and a called station via a central office. The interface unit comprises a first switch connected to the calling station in the tip and ring lines and a second switch connected to the central office in the tip and ring lines, the switches having first and second positions and wherein said signals on the tip and ring lines are connected directly between the calling station and the central office when each of the switches is in the first position. In operation, a control circuit of the line interface unit responds to detection of a busy/no answer condition at the called station for switching the first switch from its first to second position to connect a speech circuit to the calling station for issuing a prompt. After the prompt is issued, the control circuit responds to receipt of a DTMF signal or additional coinage from the calling station for switching the second switch from first to second position to connect a speed-dial circuit to the central office for dialing the voice message facility. The control unit then responds to receipt of a DTMF signal from the voice message facility for switching the first and second switches from their second positions back to their first positions to connect the calling station to the voice message facility.
First Claim
Related Publications
International Classification(s)
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Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
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| 4,674,116 Telephone line concentrator without switching matrix | 9 | 1985 | |
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| 4,696,028 PBX Intercept and caller interactive attendant bypass system | 176 | 1984 | |
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| 4,371,752 Electronic audio communication system | 215 | 1979 | |
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| 4,602,129 Electronic audio communications system with versatile message delivery | 204 | 1982 | |
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| 4,600,809 Telephone systems | 42 | 1984 | |
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| 4,766,604 Method for receiving and delivering voice messages | 109 | 1986 | |