US3883690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Junction unit alternatively providing branch line broadcasting of data and branch line selection
Assignee: AT&T Inc
•
Filing: 1973-12-19
•
Granted: 1975-05-13
•
Expires: 1993-12-19
Abstract
Abstract A symmetrical junction unit interconnects a plurality of branch lines which extend to line loops of data stations. Normally, data signals on any branch from the data station connected thereto are broadcast by the junction unit to all other branches and supervisory control signals are blocked. When it is desired to test a branch line, signaling equipment connected to one designated branch signals the junction unit to select the desired branch. The junction unit, in response thereto, permits the interchange of both data and control signals between the one designated branch and the selected branch and blocks all the unselected branches. In one embodiment, branch lines are arranged to accommodate half-duplex signaling during the normal mode and full-duplex signaling during testing.
Inventors
- 👤 Leo Michael Kolensky
- 👤 Randolph John Pilc
- 👤 Walter Rudolph Schaefer
- 👤 Allan Howard Willand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:31
CPC Classifications
H; H04; H04L; H04L43/00; H04L43/50; H04L12/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
149 words
A junction unit interconnecting a plurality of two-way branch lines, one of the branch lines extending to control equipment, the junction unit comprising, means for repeating signals received from each of the branch lines, means for broadcasting the repeated signals to all of the other branch lines, means for blocking the repeated signals, means for distinguishing between the reception of data signals and control signals from each of the branch lines and for enabling the blocking means in response to the reception of control signals, and means responsive to branch line selection signals received from the branch line extending to the control equipment for disabling the distinguishing means of the selected branch line and of the control branch line and for enabling the blocking means of each unselected branch line whereby the control branch line and the selected branch line are enabled to interchange both data and control signals.
Claim 2
Dependent Claim
149 words
A junction unit interconnecting a plurality of two-way branch lines, one of the branch lines extending to control equipment, the junction unit comprising, means for repeating signals received from each of the branch lines, means for broadcasting the repeated signals to all of the other branch lines, means for blocking the repeated signals, means for distinguishing between the reception of data signals and control signals from each of the branch lines and for enabling the blocking means in response to the reception of control signals, and means responsive to branch line selection signals received from the branch line extending to the control equipment for disabling the distinguishing means of the selected branch line and of the control branch line and for enabling the blocking means of each unselected branch line whereby the control branch line and the selected branch line are enabled to interchange both data and control signals.
Claim 3
Dependent Claim
32 words
A junction unit, in accordance with claim 1, wherein the broadcasting means includes means responsive to the selection signal responsive means for precluding the broadcast of signals to the unselected branch lines.
Claim 4
Dependent Claim
53 words
A junction unit, in accordance with claim 2, wherein the broadcasting means comprises gating means for interconnecting an outgoing side of each branch line to the repeating means of the other branch lines and the precluding means includes means for disabling the gating means connected to the outgoing sides of the unselected branches.
Claim 5
Dependent Claim
55 words
A junction unit, in accordance with claim 2, and further including means connected to each of the branch lines for limiting the reception of signals by and the broadcasting of signals to the branch line to one way at a time and wherein the selection signal responsive means includes means for disabling the limiting means.
Claim 6
Dependent Claim
139 words
A junction unit interconnecting a plurality of two-way branch lines, one of the branch lines extending to selection signaling equipment, the junction unit comprising, means for broadcasting data signals received from each of the branch lines to all of the other branch lines, means connected to each of the branch lines for limiting the reception of signals from and the broadcasting of signals to the branch line to one way at a time, and means responsive to the reception of predetermined branch line selection signals from the equipment branch line for disabling the limiting means connected to the equipment branch line and connected to the selected branch line and for precluding the broadcasting of signals to each of the unselected branch lines whereby exclusive and simultaneous two-way communication between the control line and the selected branch line is provided.
Claim 7
Dependent Claim
139 words
A junction unit interconnecting a plurality of two-way branch lines, one of the branch lines extending to selection signaling equipment, the junction unit comprising, means for broadcasting data signals received from each of the branch lines to all of the other branch lines, means connected to each of the branch lines for limiting the reception of signals from and the broadcasting of signals to the branch line to one way at a time, and means responsive to the reception of predetermined branch line selection signals from the equipment branch line for disabling the limiting means connected to the equipment branch line and connected to the selected branch line and for precluding the broadcasting of signals to each of the unselected branch lines whereby exclusive and simultaneous two-way communication between the control line and the selected branch line is provided.
Claim 8
Dependent Claim
52 words
A junction unit, in accordance with claim 5, wherein the broadcasting means comprises gating means for interconnecting an outgoing side of each branch line to incoming sides of the other branch lines and the precluding means includes means for disabling the gating means connected to the outgoing sides of the unselected branches.
Claim 9
Dependent Claim
40 words
A junction unit, in accordaNce with claim 5, wherein the limiting means includes means responsive to the reception of signals from an incoming side of each branch for blocking the broadcasting of signals to an outgoing side of the branch.
Claim 10
Dependent Claim
39 words
A junction unit, in accordance with claim 7, wherein each branch conveys data bytes, certain ones of the bytes being representative of idle conditions, and wherein the blocking means is responsive to the reception of the idle condition bytes.
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) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |