US3928729A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuitry for providing executive ringback in a PBX system in accordance with a supplied class of service
Assignee: AT&T Inc
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Filing: 1974-10-03
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Granted: 1975-12-23
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Expires: 1994-10-03
Abstract
Abstract In a telephone switching system wherein a plurality of line circuits are terminated in station sets, the line circuits are interconnectable to a plurality of trunk circuits through a multistage switching network. A call originated by a calling party to a called party, engaged in a conversation with a third party, is automatically completed at the conclusion of the conversation between the called party and the third party by ringing back the calling party and the called party provided both parties are equipped with a class of service which permits executive ringback. The ringback feature is initiated by the calling party upon receipt of a special busy signal by a flashing of his switchhook.
Inventors
- 👤 Carl Calvin Nielson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:24
CPC Classifications
H; H04; H04Q; H04Q3/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
212 words
In a telephone switching system having a plurality of line circuits terminated in station sets, said line circuits being intercoNnectable to a plurality of trunk circuits through a multistage switching network, the invention comprising executive ringback circuitry for completing a connection between a calling station and a called station at the conclusion of a connection between said called station and a third party station, said executive ringback circuitry including means for determining the class of service provided to said calling station, means for detecting a busy condition of said called station, means for determining a class of service provided to said called station, means, responsive to said calling station class of service determining means, said called station busy condition detecting means, and said called station class of service determining means, for seizing said executive ringback circuitry provided said calling station is equipped with a class of service permitting executive ringback and said called station is equipped with a class of service allowing executive ringback, and means, subsequently activated by said seizing means and responsive to a switchhook flash from said calling station, for effecting the establishment of executive ringback connections between said calling station and said called station at the conclusion of said connection between said called station and said third station.
Claim 2
Dependent Claim
212 words
In a telephone switching system having a plurality of line circuits terminated in station sets, said line circuits being intercoNnectable to a plurality of trunk circuits through a multistage switching network, the invention comprising executive ringback circuitry for completing a connection between a calling station and a called station at the conclusion of a connection between said called station and a third party station, said executive ringback circuitry including means for determining the class of service provided to said calling station, means for detecting a busy condition of said called station, means for determining a class of service provided to said called station, means, responsive to said calling station class of service determining means, said called station busy condition detecting means, and said called station class of service determining means, for seizing said executive ringback circuitry provided said calling station is equipped with a class of service permitting executive ringback and said called station is equipped with a class of service allowing executive ringback, and means, subsequently activated by said seizing means and responsive to a switchhook flash from said calling station, for effecting the establishment of executive ringback connections between said calling station and said called station at the conclusion of said connection between said called station and said third station.
Claim 3
Dependent Claim
46 words
The telephone switching system in accordance with claim 1 wherein the executive ringback circuitry further includes means for alerting said busy called station for a predetermined time interval that executive ringback is to be effected, and means for controlling the duration of said predetermined time interval.
Claim 4
Dependent Claim
55 words
The telephone switching system in accordance with claim 1 wherein the executive ringback circuitry further includes means, activated by said effecting means, for providing an executive ringback acknowledgment signal for a predetermined time interval to said calling station in response to said switchhook flash, and means for controlling the duration of said predetermined time interval.
Claim 5
Dependent Claim
39 words
The telephone switching system in accordance with claim 1 wherein the executive ringback circuitry further includes means for denying executive ringback to said calling station when said called station is busy as a result of a previous camp-on connection.
Claim 6
Dependent Claim
42 words
The telephone switching system in accordance with claim 1 wherein the executive ringback circuitry further includes means for detecting a return to an idle condition of said called station, and means for establishing a talking path between said calling and called stations.
Claim 7
Dependent Claim
75 words
The telephone switching system in accordance with claim 5 wherein the executive ringback circuitry further includes means, responsive to said switchhook flash enabling signal from said calling station, for holding said seizure of said executive ringback circuitry until said busy called station goes idle, and means, responsive to said detection of a return to an idle condition of said called station, for supplying a predetermined number of ringing signals to said calling and called stations.
Claim 8
Dependent Claim
92 words
The telephone switching system in accordance with claim 6 wherein the executive ringback circuitry further includes means, activated by said calling station going off-hook in response to said ringing signals within said predetermined number of said signals, for disconnecting said ringing signal supply means from said calling station, means for supplying an audible ringback signal to said calling station, and means, activated by said called station going off-hook in response to said ringing signals within said predetermined number of said signals, for disconnecting said ringback signal supply means from said calling station.
Claim 9
Dependent Claim
92 words
The telephone switching system in accordance with claim 6 wherein the executive ringback circuitry further includes means, activated by said called station going off-hook in response to said ringing signals within said predetermined number of said signals, foR disconnecting said ringing signal supply means from said called station, means for supplying an audible ringback signal to said called station, and means, activated by said calling station going off-hook in response to said ringing signals within said predetermined number of said signals, for disconnecting said ringback signal supply means from said called station.
Claim 10
Dependent Claim
62 words
The telephone switching system in accordance with claim 6 wherein the executive ringback circuitry further includes means for detecting a failure of said calling station to respond to said ringing signals within said predetermined number of said signals, and means, activated by said detecting means, for releasing said seized executive ringback circuitry at the termination of said predetermined number of ringing signals.
Claim 11
Dependent Claim
44 words
The telephone switching system in accordance with claim 6 wherein the executive ringback circuitry further includes means, activated by said ringing signal supply means and responsive to a return to an idle state by said calling station, for releasing said seized executive ringback circuitry.
Claim 12
Dependent Claim
134 words
Circuitry for controlling the establishment of executive ringback connections between a calling station having a class of service which permits it to effect ringback call connections and a busy called station having a class of service which permits the establishment of a ringback call connection upon the termination of a previously established call connection with a third party station, said circuitry comprising means, responsive to a call from said calling station to said called station, for detecting a busy condition of said called station, and means, subseqently activated by said detecting means and responsive to a switchhook flash from said calling station, for effecting the establishment of call connections between said calling station and said busy called station at the conclusion of said connection between said third party station and said busy called station.
Claim 13
Dependent Claim
134 words
Circuitry for controlling the establishment of executive ringback connections between a calling station having a class of service which permits it to effect ringback call connections and a busy called station having a class of service which permits the establishment of a ringback call connection upon the termination of a previously established call connection with a third party station, said circuitry comprising means, responsive to a call from said calling station to said called station, for detecting a busy condition of said called station, and means, subseqently activated by said detecting means and responsive to a switchhook flash from said calling station, for effecting the establishment of call connections between said calling station and said busy called station at the conclusion of said connection between said third party station and said busy called station.
Claim 14
Dependent Claim
86 words
Executive ringback circuitry comprising means for seizing said circuitry in response to a call from a calling station, having a class of service which permits it to effect ringback call connections, to a busy called station, having a class of service which permits the establishment of a ringback call connection upon the termination of a previously established call connection, and means, responsive to a receipt of a switchhook flash from said calling station, for establishing executive ringback connections between said calling station and said called station.
Claim 15
Dependent Claim
86 words
Executive ringback circuitry comprising means for seizing said circuitry in response to a call from a calling station, having a class of service which permits it to effect ringback call connections, to a busy called station, having a class of service which permits the establishment of a ringback call connection upon the termination of a previously established call connection, and means, responsive to a receipt of a switchhook flash from said calling station, for establishing executive ringback connections between said calling station and said called station.
Claim 16
Dependent Claim
40 words
The executive ringback circuitry in accordance with claim 12 further comprising means, activated by said establishing means, for supplying an executive ringback signal over said established connections to said calling station and said called station for a predetermined time interval.
Claim 17
Dependent Claim
87 words
The executive ringback circuitry in accordance with claim 13 further comprising means, activated upon termination of said executive ringback signal, for holding said seized executive ringback circuitry and said established connections between said calling and called stations until said called station goes idle, means for detecting a return to an idle condition of said called station, and means, responsive to said detection of a return to an idle condition of said called station, for supplying a predetermined number of ringing signals to said calling and called stations.
References Cited (Backward Citations)
US3854014A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |