EP0287369A2
Expired / Lapsed
EP
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Remote disconnection and shortcircuiting apparatus
Assignee: TTEC International Pty Ltd
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Filing: 1988-04-14
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Granted: —
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Expires: 2008-04-14
Abstract
Abstract Apparatus for remote disconnection and short-circuiting of a pair of conductors (14, 16), such as those comprising a telephone line (18), consists of a switching unit (10) and a probe unit (12). The switching unit (10) is capable of generating a tone and the tone may be sent down the pair of conductors, where the probe unit (12) is used to identify the pair. The probe unit is also able to send bursts of a signal along the pair, upon receipt of which the switching unit switches sequentially from a first mode (when the tone is applied to the conductors) to a second-mode (where the conductors are disconnected) to a third mode (where the conductors are short circuit). The apparatus is useful in line fault location and telephone apparatus installation.
Inventors
- 👤 Roger John La Salle
- 👤 Roger Hamline Stafford Riordan
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 17:56
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/30; H04M3/301
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
116 words
Apparatus for remote disconnection and short-circuiting of a pair of conductors (14,16), characterized by: a) a switching unit (10) adapted to be connected to one end of said pair of conductors, and b) a probe unit (12) adapted to be connected to the other end of said pair of conductors, said probe unit (12) having signal generation means (56) for generating a signal having predetermined characteristics, said signal being capable of being sent by said probe unit (12) along said pair of conductors (14,16), said switching unit (10) including detection means for detecting said signal, and switching means for carrying out switching operation on said pair of conductors in response to the receipt of said signal.
Claim 2
Dependent Claim
116 words
Apparatus for remote disconnection and short-circuiting of a pair of conductors (14,16), characterized by: a) a switching unit (10) adapted to be connected to one end of said pair of conductors, and b) a probe unit (12) adapted to be connected to the other end of said pair of conductors, said probe unit (12) having signal generation means (56) for generating a signal having predetermined characteristics, said signal being capable of being sent by said probe unit (12) along said pair of conductors (14,16), said switching unit (10) including detection means for detecting said signal, and switching means for carrying out switching operation on said pair of conductors in response to the receipt of said signal.
Claim 3
Dependent Claim
32 words
Apparatus according to claim 1, characterized in that the receipt of successive signals from said probe unit (12), said switching means (10) is adapted to switch between a predetermined number of modes.
Claim 4
Dependent Claim
14 words
Apparatus according to claim 2, characterized in that said switching between modes operates sequentially.
Claim 5
Dependent Claim
43 words
Apparatus according to claim 2, characterized in that said predetermined modes consist of a first mode in which a tone may be applied to said line, a second mode wherein the pair is disconnected, and a third mode wherein the pair is short-circuited.
Claim 6
Dependent Claim
21 words
Apparatus according to claim 1, characterized in that the signal generated by said probe unit is generated by an oscillator (56).
Claim 7
Dependent Claim
17 words
Apparatus according to claim 5, characterized in that the frequency of said signal is around 175 Hz.
Claim 8
Dependent Claim
17 words
Apparatus according to claim 5, characterized in that the frequency of said signal is about 150 Hz.
Claim 9
Dependent Claim
68 words
Apparatus according to claim 1, characterized in that said switching unit also includes an oscillator (20) for applying a second signal or tone to said pair, said probe unit (12) having a receiver (46) adapted to receive said second signal and to produce a technician-observable signal representative of said second signal, the variation in the intensity of said technician-observable signal being able to be used for pair identification.
Claim 10
Dependent Claim
36 words
Apparatus according to claim 8, characterized in that when said switching unit (10) is switched on, said switching unit (10) automatically re-sets to a condition where said oscillator (20) is operative to generate said second signal.
Claim 11
Dependent Claim
32 words
Apparatus according to claim 8, characterized in that said second signal is a warble tone in the range 1.5 kHz to 3 kHz, at a rate between 3 Hz and 10 Hz.
Claim 12
Dependent Claim
24 words
Apparatus according to claim 1, characterized in that each of said switching unit (10) and said probe unit (12) are hand-held and battery powered.
Claim 13
Dependent Claim
18 words
Apparatus according to claim 1, characterized in that said pair of conductors (14,16) constitutes a communications line (18).
Claim 14
Dependent Claim
16 words
Apparatus according to claim 12, characterized in that said communications line (18) is a telephone line.
Claim 15
Dependent Claim
75 words
Apparatus according to claim 1, characterized in that said detecting means is a receiver tuned to the frequency of said signal, including means to detect the voltage between said pair as a result of said signal being applied thereto and/or the signal current flowing through the short circuit, the output from the receiver being rectified, filtered, and converted into pulses which cause a stepping relay, or digital logic circuits, to cycle through the said sequence.
Claim 16
Dependent Claim
62 words
Apparatus according to claim 14, characterized in that said tuned receiver consists of a Riordan type gyrator, connected to a diode pump (30) to rectify and filter the detected signal, connected in turn to a Schmitt trigger (32), the output of which is connected to the clock input of a counter comprised of one or more flip flop digital logic circuits (34).
Claim 17
Dependent Claim
22 words
Apparatus according to claim 1, characterized in that said switching unit includes bistable relays (A,B) for use in establishing the desired connections.
Claim 18
Dependent Claim
58 words
Apparatus according to claim 13, characterized in that the output of said flip flops (34) is connected via pulse generator circuits, each of which consists of a capacitor, resistors and a transistor, to the coils of bistable relays (A,B) such that said coils are energized long enough to actuate the relays in order to reduce battery current drain.
Claim 19
Dependent Claim
57 words
Apparatus according to claim 1, characterized in that when said pair is short-circuited by said switching unit (10), a signal from said probe unit (12) is detected by a current transformer (T1) in series with the link forming said short circuit, the output of the current transformer (T1) being connected via a preamplifier to the tuned receiver.
Claim 20
Dependent Claim
18 words
Apparatus according to claim 18, characterized in that said current transformer (T1) is replaced by a series resistor.
Claim 21
Dependent Claim
20 words
Apparatus according to claim 19, characterized in that the value of said resistor is in the vicinity of 50 milliohm.
Claim 22
Dependent Claim
23 words
Apparatus according to claim 8, characterized in that said switching unit (10) automatically sets to said first mode when it is switched on.
Claim 23
Dependent Claim
20 words
Apparatus according to claim 21, characterized in that in said first mode a tone is automatically applied to said line.
Claim 24
Dependent Claim
19 words
Apparatus according to claim 8, characterized in that the means for producing said technician-observable signal is a loudspeaker (52).
Claim 25
Dependent Claim
23 words
Apparatus according to claim 8, characterized in that the means for producing said technician-observable signal is a peizoelectric transducer, to reduce power drain.
Claim 26
Dependent Claim
64 words
Apparatus according to claim 24, characterized in that the output of the high impedance amplifier (48) is fed via an ideal rectifier, acting as a frequency doubler, to the piezoelectric transducer, the purpose of the frequency doubler being to match the frequency of the identification tone more closely to the resonant frequency of the piezoelectric transducer to get the maximum effective audio signal output.
Claim 27
Dependent Claim
42 words
Apparatus according to claim 25, characterized in that the output of the frequency doubler is fed via two amplifiers out of phase to the two sides of the piezoelectric transducer, so that the effective output signal from the transducer is effectively doubled.
Claim 28
Independent Claim
74 words
A method for disconnecting and short-circuiting a pair of conductors (14,16), characterized by the steps of connecting a switching unit (10) to one end of said pair, and connecting a probe unit (12) to the other end of said pair of conductors, causing said probe unit (12) to apply a predetermined signal to said pair, said switching unit (10) being responsive to said signal to switch said conductors between a number of predetermined modes.
Claim 29
Independent Claim
74 words
A method for disconnecting and short-circuiting a pair of conductors (14,16), characterized by the steps of connecting a switching unit (10) to one end of said pair, and connecting a probe unit (12) to the other end of said pair of conductors, causing said probe unit (12) to apply a predetermined signal to said pair, said switching unit (10) being responsive to said signal to switch said conductors between a number of predetermined modes.
Claim 30
Dependent Claim
16 words
A method according to claim 27, characterized in that said switching between modes takes place sequentially.
Claim 31
Dependent Claim
45 words
A method according to claim 27, characterized in that said modes consist of a first mode in which a tone may be applied to said line, a second mode in which the line is disconnected, and a third mode in which the line is short-circuited.
Claim 32
Dependent Claim
15 words
A method according to claim 27, characterized in that said frequency is about 175 Hz.
Claim 33
Dependent Claim
15 words
A method according to claim 27, characterized in that said frequency is about 150 Hz.
References Cited (Backward Citations)
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