Patent US3601561A successfully refreshed from Google Patents.
US3601561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for applying an identifying signal to a telephone-line pair without disturbance of service
Assignee: Perkins Res & Manufacturing Co
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Filing: 1969-05-21
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Granted: 1971-08-24
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Expires: 1989-05-21
Abstract
Abstract An apparatus for applying an identifying tone to a telephoneline pair without disturbing user service comprising a line tap, electrical signal-producing means for imposing a tone on the telephone pair, and a switch circuit connected between the tapping line and the tone-producing means and responsive to potential in the telephone pair so as to selectively connect the tone-producing means to the pair when the lines are not in use as indicated by the telephone-pair potential and capacity.
Inventors
- 👤 Richard L Bennett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:40
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
107 words
An apparatus for applying an identifying tone to a telephoneline pair without disturbing user service comprising: means for tapping one wire of the pair; electrical signal-producing means for applying a tone on the pair; and switch-circuit means connected to said tapping and producing means responsive to a potential between said wire and ground so as to selectively connect said tone-producing means to said pair through said tapping means when said pair is not in use as indicated by the potential between said wire and ground, and responsive to the capacity between said wire and ground so as to connect said tone-producing means when no potential is present.
Claim 2
Independent Claim
107 words
An apparatus for applying an identifying tone to a telephoneline pair without disturbing user service comprising: means for tapping one wire of the pair; electrical signal-producing means for applying a tone on the pair; and switch-circuit means connected to said tapping and producing means responsive to a potential between said wire and ground so as to selectively connect said tone-producing means to said pair through said tapping means when said pair is not in use as indicated by the potential between said wire and ground, and responsive to the capacity between said wire and ground so as to connect said tone-producing means when no potential is present.
Claim 3
Dependent Claim
77 words
The portable unit of claim 1 wherein said switch-circuit means comprises: means for connecting said tone-producing means when the telephone pair is dead; means for disconnecting said tone-producing means when the telephone pair are alive and in use; means for connecting the tone-producing means when the telephone pair are alive but not in use; and means for disconnecting the tone-producing means when the pair is alive and the pair potential indicates the connection of a ringing generator.
Claim 4
Dependent Claim
24 words
The portable unit of claim 2 wherein said last-named means maintains said tone-producing means disconnected until said tapping means is disconnected from said pair.
Claim 5
Dependent Claim
25 words
The portable unit of claim 3 wherein said means for connecting said tone-producing means when the telephone pair are dead comprises a unijunction oscillator circuit.
Claim 6
Dependent Claim
15 words
The portable unit of claim 3 additionally including visual means for identifying said telephone-pair potential.
Claim 7
Dependent Claim
17 words
The portable unit of claim 5 additionally including a manual override switch for disconnecting said switch-circuit means.
Claim 8
Dependent Claim
10 words
The portable unit of claim 6 additionally including battery means.
Claim 9
Dependent Claim
18 words
The portable unit of claim 5 wherein said visual means for identifying said telephone-line potential comprises a voltmeter.
Claim 10
Independent Claim
155 words
An apparatus for applying an identifying tone to a telephone-line pair without disturbing user service comprising: means for tapping one of the pair; electrical signal-producing means for imposing a tone on the pair; and switch-circuit means connected to said tapping and tone-producing means responsive to potential and capacity in said pair including: means for connecting said tone-producing means when the telephone-pair potential is in the range of 0 to 5 volts, means for disconnecting said tone-producing means when the telephone-pair potential is in the range of 5 to substantially 46 volts, means for connecting the tone-producing means when the telephone-pair potential is in the range of 48 to 90 volts, and means for disconnecting the tone-producing means when the telephone-pair potential is above 90 volts, whereby said switch-circuit means selectively connects said tone-producing means to said telephone pair through said tapping means when said pair is not in use as indicated by the pair potential.
Claim 11
Independent Claim
155 words
An apparatus for applying an identifying tone to a telephone-line pair without disturbing user service comprising: means for tapping one of the pair; electrical signal-producing means for imposing a tone on the pair; and switch-circuit means connected to said tapping and tone-producing means responsive to potential and capacity in said pair including: means for connecting said tone-producing means when the telephone-pair potential is in the range of 0 to 5 volts, means for disconnecting said tone-producing means when the telephone-pair potential is in the range of 5 to substantially 46 volts, means for connecting the tone-producing means when the telephone-pair potential is in the range of 48 to 90 volts, and means for disconnecting the tone-producing means when the telephone-pair potential is above 90 volts, whereby said switch-circuit means selectively connects said tone-producing means to said telephone pair through said tapping means when said pair is not in use as indicated by the pair potential.
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) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |