US3898389A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage and/or current-sensitive loop extender
Assignee: CMC TELECOM Corp
•
Filing: 1974-05-03
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Granted: 1975-08-05
•
Expires: 1994-05-03
Abstract
Abstract A telephone loop extending circuit for aiding central office battery. There are first and second pairs of input/output terminals and first and second voltage insertion circuits corresponding to the first and second pairs of terminals. Each insertion circuit has a path for current flow coupled between the corresponding pair of terminals. Each insertion circuit has a voltage source, a controllable switch operative when enabled for switching the voltage source between terminals of the corresponding terminal pair in first and second directions of polarity and a sensing circuit for sensing an applied current flow through the corresponding path in first and second directions and responsive to such sensing for enabling the controllable switches to switch the voltage source, respectively, in the first direction or in the second direction of polarity. Additionally included is a circuit operative in response to a rapid reversal in polarity of an applied voltage between two terminals, one from each of the terminal pairs, while the voltage source is coupled in one direction of polarity for enabling the controllable switch in either of the insertion circuits to reverse the polarity in which the corresponding voltage source is coupled in between terminals of the corresponding terminal pair.
Inventors
- 👤 Thomas W Hanneman
- 👤 Frederic R Sparrevohn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:48
CPC Classifications
H; H04; H04M; H04M19/00; H04M19/001; H04M19/006
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
223 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals for connection in opposite sides of a telephone loop; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each insertion circuit having a path for current flow coupled between the corresponding pair of terminals and comprises: 1. voltage source means, 2. controllable switch means operative when enabled for switching the voltage source means between terminals of the corresponding terminal pair in first and second directions of polarity, and 3. means for sensing an applied current flow through the corresponding path in first and second directions and responsive to such sensing for enabling the controllable switch means to switch the voltage means, respectively, in the first direction or in the second direction of polarity; and c. means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while voltage source means is coupled in one direction of polarity for enabling the controllable switch means in each of the insertion circuits to reverse the polarity in which the corresponding voltage source means is coupled in between terminals of the corresponding terminal pair.
Claim 2
Dependent Claim
223 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals for connection in opposite sides of a telephone loop; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each insertion circuit having a path for current flow coupled between the corresponding pair of terminals and comprises: 1. voltage source means, 2. controllable switch means operative when enabled for switching the voltage source means between terminals of the corresponding terminal pair in first and second directions of polarity, and 3. means for sensing an applied current flow through the corresponding path in first and second directions and responsive to such sensing for enabling the controllable switch means to switch the voltage means, respectively, in the first direction or in the second direction of polarity; and c. means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while voltage source means is coupled in one direction of polarity for enabling the controllable switch means in each of the insertion circuits to reverse the polarity in which the corresponding voltage source means is coupled in between terminals of the corresponding terminal pair.
Claim 3
Dependent Claim
27 words
controllable switch means operative when enabled for switching the voltage source means between terminals of the corresponding terminal pair in first and second directions of polarity, and
Claim 4
Dependent Claim
27 words
controllable switch means operative when enabled for switching the voltage source means between terminals of the corresponding terminal pair in first and second directions of polarity, and
Claim 5
Dependent Claim
58 words
first and second transistors, each having a base electrode and an emitter-collector electrode circuit, the emitter-collector electrode circuit of the first transistor having one side coupled to a first side of the first voltage source means, the emitter-collector electrode circuit of the second transistor having one side coupled to a first side of the second voltage source means,
Claim 6
Dependent Claim
58 words
first and second transistors, each having a base electrode and an emitter-collector electrode circuit, the emitter-collector electrode circuit of the first transistor having one side coupled to a first side of the first voltage source means, the emitter-collector electrode circuit of the second transistor having one side coupled to a first side of the second voltage source means,
Claim 7
Dependent Claim
24 words
first controllable switch means operative when enabled for switching the voltage source means between the corresponding terminal pair in a first direction of polarity,
Claim 8
Dependent Claim
24 words
first controllable switch means operative when enabled for switching the voltage source means between the corresponding terminal pair in a first direction of polarity,
Claim 9
Dependent Claim
25 words
first controllable switch means operative when enabled for switching the first voltage source means between the corresponding terminal pair in a first direction of polarity,
Claim 10
Dependent Claim
25 words
first controllable switch means operative when enabled for switching the first voltage source means between the corresponding terminal pair in a first direction of polarity,
Claim 11
Dependent Claim
50 words
A telephone loop extending circuit according to claim 1 wherein said means for sensing an applied current flow comprises means for generating light responsive to the current flow and wherein said controllable switch means comprises a light responsive control means which is responsive to light from the light generating means.
Claim 12
Dependent Claim
128 words
means for sensing an applied current flow through the corresponding path in first and second directions and responsive to such sensing for enabling the controllable switch means to switch the voltage means, respectively, in the first direction or in the second direction of polarity; and c. means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while voltage source means is coupled in one direction of polarity for enabling the controllable switch means in each of the insertion circuits to reverse the polarity in which the corresponding voltage source means is coupled in between terminals of the corresponding terminal pair.
Claim 13
Dependent Claim
128 words
means for sensing an applied current flow through the corresponding path in first and second directions and responsive to such sensing for enabling the controllable switch means to switch the voltage means, respectively, in the first direction or in the second direction of polarity; and c. means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while voltage source means is coupled in one direction of polarity for enabling the controllable switch means in each of the insertion circuits to reverse the polarity in which the corresponding voltage source means is coupled in between terminals of the corresponding terminal pair.
Claim 14
Dependent Claim
97 words
A telephone loop extending circuit according to claim 1 wherein the controllable switch means comprises first and second transistors, each having base, emitter and collector electrodes, the emitter-collector electrode circuit of each of the first and second transistors being coupled between the voltage source means and one of the terminals of the corresponding terminal pair, and wherein the means for sensing an applied voltage comprises impedance means coupled between the base electrode of both of the first and second transistors in the first circuit and the base electrodes of both of the transistors in the second circuit.
Claim 15
Dependent Claim
25 words
second controllable switch means operative when enabled for switching the second voltage source means between the correspondiNg terminal pair in a second direction of polarity,
Claim 16
Dependent Claim
25 words
second controllable switch means operative when enabled for switching the second voltage source means between the correspondiNg terminal pair in a second direction of polarity,
Claim 17
Dependent Claim
24 words
second controllable switch means operative when enabled for switching the voltage source means between the corresponding terminal pair in a second direction of polarity,
Claim 18
Dependent Claim
24 words
second controllable switch means operative when enabled for switching the voltage source means between the corresponding terminal pair in a second direction of polarity,
Claim 19
Dependent Claim
23 words
first and second light responsive means for controlling current conduction through the emitter-collector electrode circuits of, respectively, the first and second transistors, and
Claim 20
Dependent Claim
23 words
first and second light responsive means for controlling current conduction through the emitter-collector electrode circuits of, respectively, the first and second transistors, and
Claim 21
Dependent Claim
166 words
first means for coupling the other side of the emitter-collector electrode circuits of the first and second transistors to a first terminal of the corresponding pair and second means for coupling a second side of each of the first and second voltage source means to the second terminal of the corresponding pair, one of the coupling means comprising first and second light generating means for sensing current flow between terminals of the corresponding terminal pair, the first light generating means being responsive to current flow between the corresponding terminals in a first direction for applying light to the first light responsive means, thereby causing the first transistor to couple the first voltage source means between terminals in a first direction of polarity, the second light generating means being responsive to current flow between terminals in a second direction for applying light to the second light responsive means, causing the second transistor to couple the second voltage source means between terminals in a second direction of polarity.
Claim 22
Dependent Claim
166 words
first means for coupling the other side of the emitter-collector electrode circuits of the first and second transistors to a first terminal of the corresponding pair and second means for coupling a second side of each of the first and second voltage source means to the second terminal of the corresponding pair, one of the coupling means comprising first and second light generating means for sensing current flow between terminals of the corresponding terminal pair, the first light generating means being responsive to current flow between the corresponding terminals in a first direction for applying light to the first light responsive means, thereby causing the first transistor to couple the first voltage source means between terminals in a first direction of polarity, the second light generating means being responsive to current flow between terminals in a second direction for applying light to the second light responsive means, causing the second transistor to couple the second voltage source means between terminals in a second direction of polarity.
Claim 23
Dependent Claim
42 words
first means coupled in between terminals of the corresponding terminal pair for sensing an applied current flow in a first direction therebetween and responsive thereto, enabling the first controllable switch means to switch the voltage means in the first direction of polarity,
Claim 24
Dependent Claim
42 words
first means coupled in between terminals of the corresponding terminal pair for sensing an applied current flow in a first direction therebetween and responsive thereto, enabling the first controllable switch means to switch the voltage means in the first direction of polarity,
Claim 25
Dependent Claim
32 words
first means for sensing an applied current flow through the corresponding path in a first direction and, responsive thereto, enabling the first controllable switch means to switch the first voltage source means,
Claim 26
Dependent Claim
32 words
first means for sensing an applied current flow through the corresponding path in a first direction and, responsive thereto, enabling the first controllable switch means to switch the first voltage source means,
Claim 27
Dependent Claim
94 words
A telephone loop extending circuit according to claim 3 wherein said means for sensing an applied current flow comprises light generating means for sensing current flow in opposite directions in the corresponding current path, and wherein said controllable switch means comprises first and second light responsive control means, the first and second light responsive control means responding to light from the first and second light generating means for applying control signals from the emitter-collector electrode circuit to the base electrode of, respectively, said first and second transistors, thereby switching the respective transistors into conduction.
Claim 28
Dependent Claim
64 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals for connection on opposite sides of a telephone loop; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each insertion circuit having a path for current flow coupled between the corresponding pair of terminals, each insertion circuit comprising:
Claim 29
Dependent Claim
64 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals for connection on opposite sides of a telephone loop; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each insertion circuit having a path for current flow coupled between the corresponding pair of terminals, each insertion circuit comprising:
Claim 30
Dependent Claim
105 words
second means for sensing an applied current flow through the corresponding circuit path in a second direction and, responsive thereto, enabling the second controllable switch means to switch the second voltage source means; and c. third means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while controllable switch means are enabled for disabling the controllable switch means then enabled and for causing the other controllable switch means in each of the insertion circuits to be enabled.
Claim 31
Dependent Claim
105 words
second means for sensing an applied current flow through the corresponding circuit path in a second direction and, responsive thereto, enabling the second controllable switch means to switch the second voltage source means; and c. third means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while controllable switch means are enabled for disabling the controllable switch means then enabled and for causing the other controllable switch means in each of the insertion circuits to be enabled.
Claim 32
Dependent Claim
115 words
second means coupled in between terminals of the corresponding terminal pair for sensing an applied current flow in a second direction therebetween and responsive thereto, enabling the second controllaBle switch means to switch the second voltage source in the second direction of polarity; and c. third means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while controllable switch means are enabled for disabling the controllable switch means then enabled and for causing the other controllable switch means in each of the booster circuits to be enabled.
Claim 33
Dependent Claim
115 words
second means coupled in between terminals of the corresponding terminal pair for sensing an applied current flow in a second direction therebetween and responsive thereto, enabling the second controllaBle switch means to switch the second voltage source in the second direction of polarity; and c. third means for sensing an applied voltage between a terminal of the first pair of terminals and a terminal of the second pair of terminals and operative in response to a rapid reversal in polarity of an applied voltage while controllable switch means are enabled for disabling the controllable switch means then enabled and for causing the other controllable switch means in each of the booster circuits to be enabled.
Claim 34
Dependent Claim
53 words
A telephone loop extending circuit according to claim 5 wherein said first and second means for sensing current comprises, respectively, first and second light generating means, and wherein said first and second controllable switch means each comprise light responsive means for responding to light from, respectively, the first and second light generating means.
Claim 35
Dependent Claim
57 words
A telephone loop extending circuit according to claim 6 wherein the light generating means of the first and second means for sensing current comprises unilateral current conductive means; and additionally comprising means for coupling the unilaterally conductive means of each insertion circuits together so that current flows through each in opposite directions in the corresponding current path.
Claim 36
Dependent Claim
44 words
A telephone loop extending circuit according to claim 6 wherein said first and second controllable switch means each further comprises switch means controlled by the corresponding light responsive means for coupling the corresponding voltage source means between the terminals of the corresponding terminal pair.
Claim 37
Dependent Claim
91 words
A telephone loop extending circuit according to claim 5 wherein each controllable switch means comprises a transistor having base, emitter and collector electrodes, the emitter-collector electrode circuits of the transistors in the first and second controllable circuits being coupled from, respectively, the first and second voltage source means to a terminal of the corresponding terminal pair, and wherein the third means comprises impedance means coupled from the base electrodes of the transistors in the first voltage insertion circuit to the base electrode of the transistors in the second voltage insertion circuit.
Claim 38
Dependent Claim
64 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals for connection in opposite sides of a telephone loop; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each insertion circuit having a path for current flow coupled between the corresponding pair of terminals, each insertion circuit comprising:
Claim 39
Dependent Claim
64 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals for connection in opposite sides of a telephone loop; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each insertion circuit having a path for current flow coupled between the corresponding pair of terminals, each insertion circuit comprising:
Claim 40
Dependent Claim
37 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each comprising:
Claim 41
Dependent Claim
37 words
A telephone loop extending circuit for aiding central office battery comprising: a. first and second pairs of input/output terminals; b. first and second voltage insertion circuits corresponding to said first and second pairs of terminals, each comprising:
Claim 42
Dependent Claim
58 words
A telephone loop extending circuit according to claim 11 wherein said first and second light responsive means comprise, respectively, first and second unilateral current conductive means for connecting the unilateral conductive means so that current flowing in first and second directions between terminals of the corresponding terminal pair passes through, respectively, the first and second unilaterally conductive means.
Claim 43
Dependent Claim
85 words
A telephone loop extending circuit according to claim 11 wherein said first and second voltage source means comprise first and second serially connected capacitor means and a full wave bridge rectifier circuit for applying signals across the serially connected capacitor means, the second side of each of the voltage source means being at the common side of the capacitor means and the first side of the first and second voltage source means being at the other side, respectively, of the first and second capacitor means.
Claim 44
Dependent Claim
42 words
A telephone loop extending circuit according to claim 11 comprising resistive impedance means coupled from the base electrodes of both of the transistors in the first insertion circuit to the base electrodes of both of the transistors in the second insertion circuit.
Claim 45
Dependent Claim
36 words
A telephone loop extending circuit according to claim 11 wherein the first and second light responsive means each comprises an input/output circuit coupled from the base electrode to the emitter-collector electrode circuit of the corresponding transistor.
Claim 46
Dependent Claim
23 words
A telephone loop extending circuit according to claim 15 wherein the first and second light responsive means each comprises a photo-sensitive transistor element.
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) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |