CN1017391B - Subminiature extending protector for communication exchanger - Google Patents

Subminiature extending protector for communication exchanger

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Publication number
CN1017391B
CN1017391B CN 91106939 CN91106939A CN1017391B CN 1017391 B CN1017391 B CN 1017391B CN 91106939 CN91106939 CN 91106939 CN 91106939 A CN91106939 A CN 91106939A CN 1017391 B CN1017391 B CN 1017391B
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China
Prior art keywords
bell
present
isolating transformer
secondary winding
bag
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Expired
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CN 91106939
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Chinese (zh)
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CN1053721A (en
Inventor
王宝珠
石峰
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Individual
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Individual
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Application filed by Individual filed Critical Individual
Priority to CN 91106939 priority Critical patent/CN1017391B/en
Publication of CN1053721A publication Critical patent/CN1053721A/en
Publication of CN1017391B publication Critical patent/CN1017391B/en
Expired legal-status Critical Current

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Abstract

The present invention relates to a distance extending safety device of communication exchange equipment, particularly to a small distance extending safety device. The device comprises a photocell circuit, a photoelectric coupler, an isolating transformer, an automatic telephone, an exchanger, etc. The device is characterized in that the primary isolating transformer and the secondary isolating transformer are respectively formed by connecting primary windings and secondary windings of a ringing-frequency line packet and an audio-frequency line packet in series; bidirectional trigger diodes are connected in series on the primary windings and the secondary windings which are connected in series; the photocell circuit is connected with the emitting part of the photoelectric coupler; the receiving part of the photoelectric coupler is connected with the secondary windings of the isolating transformer; voltage dependent resistors are respectively connected in parallel on the input end and the output end of the device. The device has a distance extending function and a safety function.

Description

Subminiature extending protector for communication exchanger
The present invention relates to prolonging apart from protective device of a kind of communication exchange equipment, particularly small-sized prolongs apart from protective device.
Existing communication exchange equipment is defined as 1K Ω-2K Ω (comprising the telephone set D.C. resistance) usually to the loop resistance value of communication line, to the special user of loop resistance above 2K Ω, then must install remote extension device additional.This extension device volume is big, circuit is quite complicated, costs an arm and a leg, and can only be fitted to the outlet of the trunk subscriber of communication switchboard one side, and can not use at user side, range of application is restricted, and some developed country is as prolonging apart from inserting dish that Americanized Harris-2020 stored-program control exchange is equipped with, its circuit is also very complicated, cost an arm and a leg, buy 1000 program control expenses and can only buy the individual slotting dish of distance that prolongs of 10-20, general Office of the Telecommunications Authority is difficult to acceptance.The protector of existing communication exchange equipment is only used the discharge type protector, its shortcoming is when dangerous voltage is scurried into communication equipment, discharger synchronous discharge fully, the probability of burning apparatus is still very high, and when discharging current is big, the heat insurance is blown, and must be repaired by the workman, is difficult to guarantee that communication is unblocked.When particularly it was installed on the communication equipment that uses higher-pressure regions such as power plant, electric substation, still can raise because of the earth potential of thunderbolt or the generation of power line ground connection burnt out through discharger counterattack equipment, thereby it is badly damaged that communication equipment is suffered.In view of this, all be recommended in high voltage region among overseas call, telegram Advisory Board (CCITT) file and the international GB-6830-86 and use insulated isolation transformer as security personnel's safeguard procedures, its effect is best.But present insulated isolation transformer prolongs with old production model always, it is for satisfying the bell frequency signal that should transmit 25HZ, guarantee voice-frequency signal sending allowance little (requirement is less than or equal to 0.5db) again to 300HZ-3400HZ, so it must adopt big iron core and the heavy gauge wire of 50W-100W to make, its volume is big like this, Heavy Weight, the price height, install and use all inconveniently, and it only is applicable on the magnetic-type communication equipment, and can't be used on the present widely used automated communications switching equipment.In addition, above-mentioned existing prolonging apart from the function singleness of device and protector can not lump together.
Purpose of the present invention is exactly in order to address the above problem, and provides a kind of microminiature of communication exchange equipment to prolong apart from protector.
Technical solution of the present invention as shown in the figure.
Fig. 1 is the electrical schematic diagram that adopts the double-iron core isolating transformer among the present invention;
Fig. 2 is the electrical schematic diagram that adopts single iron core isolating transformer among the present invention.
Such as Fig. 1, photocell circuit 2, photoelectrical coupler 3, isolating transformer 4 and automatic telephone 1 and switch 5 etc. have been the present invention includes, and photoelectrical coupler 3 is in series with isolating transformer 4, be characterized in, the primary and secondary of isolating transformer 4 is composed in series by armature winding I, III and secondary windings II, the IV of bell frequency line bag and tone frequency channel wire bag respectively, and a bell frequently end of the armature winding I of line bag passes through bidirectional trigger diode DB1And capacitor C2Series arm be connected with the input a of apparatus of the present invention, the bell frequently other end of line bag armature winding I is connected with an end of tone frequency channel wire bag armature winding III, its tie point passes through capacitor C1Also be connected another input b of another termination apparatus of the present invention of armature winding III, the light emitting diode D of the radiating portion of photoelectrical coupler 3 with the input a of apparatus of the present invention1、D 2Negative pole by potentiometer W1Meet the input a of apparatus of the present invention, D1、D 2Positive pole by choke coil L1Connect the positive pole of the nickel-cadmium cell E in the photocell circuit 2, the negative pole of nickel-cadmium cell E is by choke coil L2Connect the frequently intermediate connection point of line bag armature winding I and tone frequency channel wire bag armature winding III of bell in the isolating transformer 4. A bell frequently end of the secondary windings II of line bag passes through bidirectional trigger diode DBAnd capacitor C4Series arm be connected with the output c of apparatus of the present invention, the bell frequently other end of line bag secondary windings II is connected with an end of tone frequency channel wire bag secondary windings IV, its tie point passes through capacitor C3Also be connected with the output c of apparatus of the present invention, another output d of another termination apparatus of the present invention of secondary windings IV, photoelectrical coupler 3 receiving units are oppositely and the photoelectric receiving tube G that connects1、G 2An end by potentiometer W2Meet the output c of apparatus of the present invention, G1、G 2Another termination bell tie point of line bag secondary windings II and tone frequency channel wire bag secondary windings IV frequently, input a, the b of apparatus of the present invention and output c, d among also meet a piezo-resistance WYH4、WYH 6, its input a, b are connected with relaying door 1 of automatic telephone or dispatching telephone control board by communication cable 6, and its output c, d pass through communication cable 6 ' be connected with switch (or the carrier terminal equipment of tape swap function, microwave machine) 5. In apparatus of the present invention, bell frequently line bag adopts common silicon steel sheet iron core, and the tone frequency channel wire bag adopts the iron steel oxygen iron core of high permeability, and bell frequently the number of turn of the armature winding I of line bag be greater than the number of turn of its secondary windings II, to reach ring signal in capacitor C2、C 4The compensation of upper loss, bell frequently line bag can be selected thinner lead, and the primary and secondary winding III of tone frequency channel wire bag, the turn ratio of IV are 1: 1.
Apparatus of the present invention also can adopt the isolating transformer of single iron core, such as Fig. 2, the connection of the primary wire of its isolating transformer 4 connects identical with the primary wire of double-iron core isolating transformer, the bell of isolating transformer 4 frequently line bag secondary windings II one end is connected another termination capacitor C of secondary windings II with the output c of apparatus of the present invention5An end, simultaneously by potentiometer W2Meet photoelectric receiving tube G reverse in the photoelectrical coupler 3 and that connect1、G 2An end, G1、G 2The other end and capacitor C5The other end links to each other and is connected another output d of another termination apparatus of the present invention of secondary windings IV with an end of tone frequency channel wire bag secondary windings IV. Here, the number of turn of bell frequency line bag armature winding I is greater than the number of turn sum of bell frequency line bag secondary windings II and tone frequency channel wire bag secondary windings IV, to reach ring signal in capacitor C2、C 5The compensation of upper loss, and the ratio of the number of turn of tone frequency channel wire bag armature winding III and the number of turn sum of bell, tone frequency channel wire bag secondary windings II, IV is 1: 1.
Operation principle of the present invention such as Fig. 1, when switch 5 was sent bell signal, its bell was pressed by telecommunication cable 6 ' be added to c, the d two ends of apparatus of the present invention, because the higher (90V ± 15V) of ringing signal voltage, and its frequency lower (25HZ), then this signal makes bidirectional trigger diode DB IIAnd capacitor C 4The series arm conducting, and C 3Big to the bell impedance that presents of signal frequently, then bell frequently signal be added on the secondary winding II, IV of isolating transformer 4, so also obtain bell frequency voltage on its elementary winding I, III, then make bidirectional trigger diode DB again IAnd capacitor C 2The series arm conducting, and capacitor C 1The impedance that bell frequency signal is presented is big, then bell frequency signal is added to a, the b two ends of apparatus of the present invention, make automatic telephone 1 receive bell signal, the transmission of bell signal mainly is to finish by the bell frequency line bag of isolating transformer 4, because the tone frequency channel wire bag is very little to the impedance that bell signal presents, be almost short circuit.
Automatic telephone 1 receives bell signal and can converse, behind the off-hook, be equivalent to the phone dc impedance through telecommunication cable 6 and a, b two ends of receiving apparatus of the present invention, the then radiating portion conducting of photoelectrical coupler 3, nickel-cadmium cell E is to the light-emitting diode D of photoelectrical coupler 3 1, D 2Power supply is sent light signal, choke L 1, L 2Be the noise that is used for controlling power supply, because the photoelectric receiving tube G of photoelectrical coupler 3 1, G 2All the time the DC-voltage supply of being brought by switch 5 after then it receives light signal, wherein adds a conducting of positive bias, makes switch 5 be in normal operating conditions.Because audio signal voltage low (less than 1V), then it can not trigger bidirectional trigger diode DB to frequency height (300-3400HZ) IConducting, and again because C 2Every straight effect, make DB I, C 2Series arm be in open-circuit condition, audio signal is just passed through capacitor C 1Elementary winding III through the tone frequency channel wire bag of isolating transformer 4 is transferred on the secondary winding IV of tone frequency channel wire bag at 1: 1, and this audio signal still can not trigger bidirectional trigger diode DB IIConducting can only be passed through capacitor C 3Deliver to c, the d two ends of apparatus of the present invention, be sent to switch 5, both sides converse.
When automatic telephone 1 caller, the dc impedance that is equivalent to phone behind the off-hook is added to a of apparatus of the present invention, b two ends, makes the transmitting tube D of photoelectrical coupler 3 1, D 2Conducting, its receiving tube G 1, G 2In add an also conducting of positive bias, automatic telephone 1 can dial, automatic telephone 1 sends DC pulse during dialing, the transmitting tube D of photoelectrical coupler 3 1, D 2End synchronously or conducting with the dialing DC pulse, send the DC pulse light signal to photoelectric receiving tube G 1, G 2, make G 1, G 2In add positive bias also synchronously by or conducting, thereby send dc pulse signal to switch 5, choose called user, called party's off-hook can be conversed, communication process was identical when its communication process and aforementioned automatic telephone 1 were called.
In apparatus of the present invention, capacitor C 2, C 4Capacity Ratio C 1, C 3Much bigger, C 2, C 4Both play stopping direct current, and can transmit the bell frequency signal of 25HZ again, C 1, C 3The voice signal of main transmission 300-34000HZ.Bidirectional trigger diode DB I, DB IIAll be in open-circuit condition when static no bell is pressed or conversed, their model is 1S1236 or 1S1719, DB I, DB IIAlso can use other pressure-sensitive device instead replaces.Photoelectrical coupler 3 also can adopt the photoelectrical coupler that is made of optical fibre tube.Photocell Eg and diode D are removed and be connected in the two ends of nickel-cadmium cell E in photocell circuit 2 3Series arm outside, also with two outputs of voltage stabilizing circuit WY and connect, the output of the input termination bridge rectifier block D of voltage stabilizing circuit WY, the input of bridge rectifier block D connects the two ends of the elementary winding I of bell frequency line bag in the isolating transformer 4, can to nickel-cadmium cell E charging, can also charge to nickel-cadmium cell E except that photocell Eg like this from the bell elementary winding I taking-up of line bag frequently part ring electric energy.
When the user surpasses the required standard value because of its loop resistances of reason such as circuit length, if apparatus of the present invention are contained in switch 5 one sides, can be with potentiometer W 1Transfer to zero ohm, if apparatus of the present invention are contained in automatic telephone 1 one sides, then with potentiometer W 2Transfer to zero ohm, then be equivalent to regulate circuit loop resistance value and reduce, make both sides' normal talking.If apparatus of the present invention are installed in the middle part of the communication line between automatic telephone 1 and the switch 5, with potentiometer W 1, W 2All transfer to zero ohm, then the communication distance of Yan Changing is longer.Suppose that circuit loop resistance value exceeds standard value 250-290 Ω, just be equivalent to subscribers feeder (0.7 mm dia) and increased by five-six kilometers, because the loop resistance value of one kilometer long of the order wire of 0.7 mm dia is 48 ohm.At present, automatic telephone is tending towards the function with automatic gain, just when the big speech attenuation of loop resistance is big, has the function of regulating the amount of declining, apparatus of the present invention then can be saved auto-gain circuit, even circuit loop resistance overshoot standard value, after having adorned apparatus of the present invention, can make call completion ratio reach 100%, can guarantee sound clarity again.
When be struck by lightning, during phenomenon such as power line single-phase short circuit ground connection or forceful electric power interference, can cause that dangerous high pressure scurries into telephone and switched communication equipment, apparatus of the present invention are owing to adopted the isolating transformer 4 and the photoelectrical coupler 3 of high insulation, their isolation voltage all reaches 7000 volts, and apparatus of the present invention two ends also and be connected to piezo-resistance WYH in addition 4, WYH 5, make its insulation blocking performance reach higher standard, protected communication equipment to exempt from damage.
Apparatus of the present invention shown in Figure 2, its operation principle and Fig. 1's is basic identical, because it adopts single iron core isolating transformer, when switch 5 was sent bell signal, this signal was by bell frequency line bag secondary winding II, the capacitor C of isolating transformer 4 5Be transferred to the bell frequently elementary winding I and the III of line bag and tone frequency channel wire bag with tone frequency channel wire bag secondary winding IV, make bidirectional trigger diode DB IAnd capacitor C 2The series arm conducting, automatic telephone 1 receives bell signal, can converse behind automatic telephone 1 off-hook, and voice signal is transferred to the secondary winding II and the IV of bell, tone frequency channel wire bag at 1: 1 through the elementary winding III of the tone frequency channel wire bag of isolating transformer 4, both sides are conversed, capacitor C 5Can also can pass through voice signal by bell frequency signal here.
Apparatus of the present invention had both had to prolong apart from function and had also had protection function, the circuit loop resistance value height of its adaptation, potentiometer W in apparatus of the present invention 1Or W 2When transferring to zero ohm, be equivalent to the telephone set dc impedance and reduced about 250-290 ohm (the phone dc impedance is 300 ohm), thereby make speech range prolong 5-6 kilometer (0.7 millimeter line footpath) again than standard value, this means when the communication line distance does not increase, can select the littler communication conductor in line footpath for use, thereby save the precious metal material, reduce the cost of communication line.Apparatus of the present invention can be isolated high potential effectively; prevent that high potential from scurrying into communication exchange equipment and telephone set; the user in protection equipment and user's safety, particularly electric power system and other high-voltage regions or many thunders and lightnings area, its effect is more outstanding than the discharge type protector.Apparatus of the present invention have adopted first in the world that volume is minimum, speech impedance symmetry, the bell insulated isolation transformer of asymmetry compensation frequently, thereby have solved that existing isolating transformer volume is big, Heavy Weight, expensive common fault, remarkable in economical benefits.Apparatus of the present invention are as long as light exists, and photocell just can charge to nickel-cadmium cell all the time, also utilizes part ring electric energy to charge to nickel separation cell simultaneously, thereby makes apparatus of the present invention possess sufficient uninterrupted power supply.Apparatus of the present invention are used extremely flexible.Both can be used on switch trunk subscriber inlet, also can directly receive the subsets inlet, or be contained in and make band in the telephone casing and prolong telephone set, also can be made into the jumbo network structure of multichannel number, and concentrated and use apart from protection function.The noise that apparatus of the present invention produce on can also cadmium off-line road for balance, the relatively poor circuit of symmetry, can make its performance improve, thereby improve speech quality.

Claims (8)

1, a kind of microminiature of communication exchange equipment is prolonged apart from protector, it includes photocell circuit 2, photoelectrical coupler 3, isolating transformer 4, and photoelectrical coupler 3 is in series with isolating transformer 4, the primary and secondary that it is characterized in that isolating transformer 4 is composed in series by elementary winding I, III and secondary winding II, the IV of bell frequency line bag and tone frequency channel wire bag respectively, and a bell end of the elementary winding I of line bag frequently passes through bidirectional trigger diode DB IAnd capacitor C 2Series arm be connected with the input a of apparatus of the present invention, the other end of elementary winding I is connected with elementary winding III one end of tone frequency channel wire bag, its tie point passes through capacitor C 1Also be connected another input b of another termination apparatus of the present invention of elementary winding III, the Light-Emitting Diode D of photoelectrical coupler 3 radiating portions with the input a of apparatus of the present invention 1, D 2Negative pole by potentiometer W 1Meet the input a of apparatus of the present invention, D 1, D 2Positive pole by choke L 1Connect the positive pole of the nickel-cadmium cell E in the photocell circuit 2, the negative pole of E is by choke L 2Connect the intermediate connection point of the elementary winding I of line bag and the elementary winding III of tone frequency channel wire bag frequently of bell in the isolating transformer 4, bell frequently an end of line bag secondary winding II by bidirectional trigger diode DB 1And capacitor C 4Series arm be connected with the output C of apparatus of the present invention, the bell frequently other end of line bag secondary winding II is connected with an end of tone frequency channel wire bag secondary winding IV, its tie point passes through capacitor C 3Also be connected with the output C of apparatus of the present invention, another output d of another termination apparatus of the present invention of secondary winding IV, photoelectrical coupler 3 receiving units are oppositely and the photoelectric receiving tube G that connects 1, G 2An end by potentiometer W 2Meet the output C of apparatus of the present invention, G 1, G 2Another termination bell tie point of line bag secondary winding II and tone frequency channel wire bag secondary winding IV frequently, between input a, the b of apparatus of the present invention and output c, the d each and meet a piezo-resistance WYH A, WYH B, its input a, b are connected with relaying door 1 of automatic telephone or dispatching telephone control board by telecommunication cable 6, and its output c, d pass through telecommunication cable 6 ' be connected with main exchange (or the carrier terminal equipment of tape swap function, microwave machine) 5.
2, prolong apart from protector by the microminiature of the described communication exchange equipment of claim 1, it is characterized in that bell frequency line bag and tone frequency channel wire bag on the described isolating transformer 4 adopt double-iron core, bell line bag frequently adopts common silicon steel sheet iron core, the tone frequency channel wire bag adopts the iron steel oxygen iron core of high permeability, and the number of turn of the elementary winding I of bell frequency line bag is greater than the number of turn of its secondary winding II, bell line bag frequently can be selected thinner lead for use, and the primary and secondary winding III of tone frequency channel wire bag, the turn ratio of IV are 1: 1.
3, prolong apart from protector by the microminiature of the described communication exchange equipment of claim 1, it is characterized in that isolating transformer 4 also can adopt single iron core in apparatus of the present invention, the connection of the primary wire of its isolating transformer 4 connects identical with the primary wire of double-iron core isolating transformer, the bell of isolating transformer 4 line bag secondary winding II one end frequently is connected another termination capacitor C of secondary winding II with the output c of apparatus of the present invention 5An end, simultaneously by potentiometer W 2Connect in the photoelectrical coupler 3 oppositely and the photoelectric receiving tube G that connects 1, G 2An end, G 1, G 2The other end and capacitor C 5The other end links to each other and is connected another output d of another termination apparatus of the present invention of secondary winding IV with an end of tone frequency channel wire bag secondary winding IV.
4, prolong apart from protector by the microminiature of the described communication exchange equipment of claim 3, the number of turn of the bell frequency line bag elementary winding I of its feature in described single iron core isolating transformer 4 is greater than the number of turn sum of bell frequency line bag secondary winding II and tone frequency channel wire bag secondary winding IV, and the number of turn of the elementary winding III of tone frequency channel wire bag is 1: 1 with the ratio of the number of turn sum of bell, tone frequency channel wire bag secondary winding II, IV.
5, prolong apart from protector by the microminiature of claim 1,3 described communication exchange equipments, it is characterized in that bidirectional trigger diode DB used in the circuit I, DB IIAlso can use other pressure-sensitive device instead replaces.
6, prolong apart from protector by the microminiature of claim 1,3 described communication exchange equipments, it is characterized in that also can adopting the photoelectrical coupler that constitutes by optical fibre tube at photoelectrical coupler 3.
7, prolong apart from protector by the microminiature of claim 1,3 described communication exchange equipments, it is characterized in that the two ends of the nickel-cadmium cell E in photocell circuit 2 and be connected to photocell E 9With diode D 3Series arm, simultaneously also with two outputs of voltage stabilizing circuit WY and connect, the output of the input termination bridge rectifier block D of voltage stabilizing circuit WY, the input of bridge rectifier block D connects in the isolating transformer 4 the bell two ends of the elementary winding I of line bag frequently.
8, prolong apart from protector by the microminiature of claim 1,3 described communication exchange equipments, it is characterized in that apparatus of the present invention can be contained in switch 5 one sides, also can be contained in automatic telephone 1-side, also can be contained in the middle part of the communication line between automatic telephone 1 and the switch 5.
CN 91106939 1991-02-23 1991-02-23 Subminiature extending protector for communication exchanger Expired CN1017391B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 91106939 CN1017391B (en) 1991-02-23 1991-02-23 Subminiature extending protector for communication exchanger

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 91106939 CN1017391B (en) 1991-02-23 1991-02-23 Subminiature extending protector for communication exchanger

Publications (2)

Publication Number Publication Date
CN1053721A CN1053721A (en) 1991-08-07
CN1017391B true CN1017391B (en) 1992-07-08

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CN 91106939 Expired CN1017391B (en) 1991-02-23 1991-02-23 Subminiature extending protector for communication exchanger

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8810059B2 (en) * 2010-04-29 2014-08-19 Texas Instruments Incorporated Effective low voltage to medium voltage transmission on PRIME band

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CN1053721A (en) 1991-08-07

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