US3964048A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Communicating over power network within a building or other user location
Assignee: GENERAL PUBLIC UTILITIES CORP
•
Filing: 1974-01-28
•
Granted: 1976-06-15
•
Expires: 1994-01-28
Abstract
Abstract Power lines within a building or other user location are connected through a fuse and a filter to an external power grid that supplies power at the usual 50 Hz or 60 Hz. Communications apparatus such as a central computer and a number of typewriters is connected to the power lines within the building at at least two locations and transmits communications signals over the power lines. The communications signals have a frequency different from the frequency of the electrical power supplied by the external power grid and preferably in the audio range. The filter is tuned to pass the electrical power but substantially to block passage of the communications signals. Two important advantages are that the power lines within the building double as communications lines and that the building presents a purely resistive load to the external power grid, so that the grid has an improved power factor.
Inventors
- 👤 Joe F. Lusk
- 👤 William H. Rood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:04
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/54; H04B3/56; H04B2203/00; H04B2203/54; H04B2203/5429; H04B2203/5433; H04B2203/545; H04B2203/5462; H04B2203/5491
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
170 words
Apparatus comprising an external power grid for delivering electrical power at a given frequency to a user location such as a building, power lines within the user location connected to the external power grid for distributing electrical power within the user location, communications means at at least two stations within the user location connected to the power lines within the user location and adapted to transmit communications signals over the power lines, the communications signals having a frequency different from the frequency of the electrical power supplied by the external power grid, and filter means inserted in series between the external power grid and the power lines within the user location, the filter means being tuned to present a closed circuit to the electrical power and thus to pass the electrical power but present substantially an open circuit to the communications signals and thus substantially to block passage of the communications signals, whereby the user location is isolated from the external power grid at the frequency of the communications signals.
Claim 2
Dependent Claim
170 words
Apparatus comprising an external power grid for delivering electrical power at a given frequency to a user location such as a building, power lines within the user location connected to the external power grid for distributing electrical power within the user location, communications means at at least two stations within the user location connected to the power lines within the user location and adapted to transmit communications signals over the power lines, the communications signals having a frequency different from the frequency of the electrical power supplied by the external power grid, and filter means inserted in series between the external power grid and the power lines within the user location, the filter means being tuned to present a closed circuit to the electrical power and thus to pass the electrical power but present substantially an open circuit to the communications signals and thus substantially to block passage of the communications signals, whereby the user location is isolated from the external power grid at the frequency of the communications signals.
Claim 3
Dependent Claim
46 words
Apparatus according to claim 1 wherein the communications means comprises terminals adapted for connection to a computer and at least one typewriter, each terminal being connected to the power lines within the user location and adapted to transmit and receive communications signals over the power lines.
Claim 4
Dependent Claim
34 words
Apparatus according to claim 1 wherein the frequency of the electrical power is substantially within the range of 50 Hz to 60 Hz and the frequency of the communications signals is above 60 Hz.
Claim 5
Dependent Claim
17 words
Apparatus according to claim 3 wherein the frequency of the communications signals is in the audio range.
Claim 6
Dependent Claim
21 words
Apparatus according to claim 1 wherein the filter means comprises inductor means and capacitor means connected in series with each other.
Claim 7
Dependent Claim
20 words
Apparatus according to claim 5 further comprising fuse means connected in series with the inductor means and the capacitor means.
Claim 8
Dependent Claim
106 words
A power grid for delivering electrical power at a given frequency to a plurality of user locations and, in series with each of said user locations, filter means tuned to said given frequency in order to present a closed circuit to the electrical power and thus readily to pass the electrical power to said user locations but to present substantially an open circuit to signals of other frequencies and thus substantially to block the passage of signals of other frequencies, said user locations presenting a substantially resistive load to the power grid and the user locations being isolated from the power grid at said other frequencies.
Claim 9
Dependent Claim
106 words
A power grid for delivering electrical power at a given frequency to a plurality of user locations and, in series with each of said user locations, filter means tuned to said given frequency in order to present a closed circuit to the electrical power and thus readily to pass the electrical power to said user locations but to present substantially an open circuit to signals of other frequencies and thus substantially to block the passage of signals of other frequencies, said user locations presenting a substantially resistive load to the power grid and the user locations being isolated from the power grid at said other frequencies.
References Cited (Backward Citations)
US1607668A
Cited
US1874142A
Cited
US2048091A
Cited
US2192061A
Cited
US2481915A
Cited
US3483546A
Cited
US3659280A
Cited
US3689886A
Cited
US3702460A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-15 | 1979-12-15 | 1980-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-15 | 1983-12-15 | 1984-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-15 | 1987-12-15 | 1988-06-15 | $7700.00 | Window Closed / Lapsed |