CN2293160Y - Theft-proof puzzle lock for telephone - Google Patents

Abstract

The utility model discloses a theft-proof puzzle lock for telephone comprising a polarity inversion, an off-hook check, a power regulated voltage, a double acoustic frequency decipher, a disturb output, a single chip computer, etc. The utility model is characterized in that the utility model adopts a voltage reducing detection circuit formed by triodes and peripheral elements to match with the reset circuit of incoming call ringing formed by triodes and peripheral elements and also match with the null detection circuit of incoming call ring drown out. The theft telephone off-hook is judged by the single chip computer direct generating interfering signals to restrict outdoor dialing. The utility model has the advantages of reliable function, simple and reasonable circuit and low cost. The utility model is can be used for the situation needing external line theft proofing and the situation of indoor telephone locking.

Description

The phone anti-theft puzzle lock

The utility model relates to a kind of antitheft and indoor phone call-out limitation device of outdoor circuit of telephone communication circuit, and is particularly a kind of by monolithic processor controlled phone anti-theft puzzle lock.

Existingly utilize monolithic processor controlled phone anti-theft puzzle lock, its anti-theft circuit (outdoor limit is dialled circuit) and the partly just combination of machinery of single-chip microcomputer coded lock do not give full play to the Based Intelligent Control function of single-chip microcomputer, thereby anti-theft effect are unsatisfactory.For example utility model patent 95202863.8 is disclosed, its outdoor circuit limit is dialled control that circuit adopts general warning IC to accept a general step-down testing circuit and is produced limit and dial interference signal, the invention technological component is not high enough, thereby effect is also undesirable, through experiment group effect is not almost limit in the pulse dialing of outdoor circuit, be that outdoor phone adopts pulse dialing can accurately put through phone, only play the effect of disturbing conversation; And, have under the situation of single-chip microcomputer, also to adopt general warning IC, do not give full play to the function of single-chip microcomputer, the circuit complexity, inadequately rationally, function is reliable inadequately, increased cost.

The purpose of this utility model is to avoid the deficiencies in the prior art, a kind of pulse and dual-tone dialing that can limit outdoor circuit fully is provided, again can by the user set up on their own indoor phone the restriction number, set unlocking cipher, alert anxious number is unrestricted, and circuit advantages of simple, cost are low, the phone anti-theft puzzle lock of reliable in function.

The purpose of this utility model is achieved by the following scheme: adopt the step-down testing circuit of being made up of triode and peripheral cell thereof 4 to cooperate the incoming call ring reset circuit of being made up of triode and peripheral cell thereof 5, and cooperate the electric bell of forming by two resistance of cross-over connection between phone inlet wire one end and input pin of single-chip microcomputer, the phone inlet wire other end and reversal output negative pole that comes to press zero cross detection circuit 9, directly produce interference signal by single-chip microcomputer and limit outdoor dialing by disturbing output circuit.In the step-down testing circuit 4, divider resistance R4 one termination reversal output cathode, an end is connected with R5, transistor base, the R5 other end with triode T2 emitter, promptly " " (common port) link to each other; Triode T2 collector electrode connects power supply by resistance R 6, and collector electrode also links to each other with the end of C9, the positive pole of diode D1, another termination of C9 " ", the negative pole of diode D1 connects the base stage of the triode T6 of reset circuit 5.In the incoming call ring reset circuit 5, divider resistance R11 one end links to each other with the reversal output cathode, the other end and resistance R 12, triode T6 base stage links to each other, R12 one termination triode T6 emitter, triode T6 collector electrode is by the positive pole of resistance R 13 with diode D3, reset terminal 4 pin of resistance R 14 1 ends and single-chip microcomputer link to each other, collector electrode also links to each other with electric capacity one end, the electric capacity other end links to each other with emitter, emitter links to each other with output pin 2 pin of single-chip microcomputer, one end of the negative pole of diode D3 and resistance R 14 links to each other with power supply, the positive pole of diode D2 links to each other with another output pin 1 pin of single-chip microcomputer, and negative pole links to each other with resetting pin 4 pin.Come electric bell to press in the zero cross detection circuit 9, a resistance cross-over connection is arranged between phone inlet wire one end and polarity transformation circuits negative pole, input pin of single-chip microcomputer is by the answer the call other end of inlet wire of a resistance.

The utility model is described in detail below in conjunction with accompanying drawing (embodiment).

Fig. 1 is a functional-block diagram of the present utility model.

Fig. 2 is circuit theory diagrams of the present utility model.

Among Fig. 1, the utility model by polarity transformation circuits 1, off-hook detection circuit 2, power supply stabilization circuit 3, step-down testing circuit 4, incoming call ring reset circuit 5, double-tone frequently decoding circuit 6, disturb output circuit 7, single-chip microcomputer 8, come electric bell to press zero cross detection circuit 9 etc. partly to form.

Below with reference to Fig. 1, Fig. 2 describes: outside line IN provides operating current by the polarity transformation circuits be made up of rectifier bridge B1 1 to complete machine, and by complementary multiple tube (by T3, T4 forms), resistance R 7, the power supply stabilization circuit 3 that zener diode Z1 and capacitor C 8 are formed partly provides power supply to single-chip microcomputer IC2 and double-tone frequency decoding circuit IC1 etc., wherein the power supply of IC1 also is subjected to the output pin 18 foot control systems of IC2 by triode switch T5, connect the power supply of IC1 during receiver off-book dialing indoors, other times then cut off the power supply of IC1, to reduce shunting, improve the speech quality of indoor phone to indoor phone.At ordinary times, single-chip microcomputer is in sleep state, 1～2 pin output low level of IC2, and the incoming call ring reset circuit of being made up of triode T6, resistance R 11～R14, capacitor C 5 and diode D2～D3 5 is in the T6 cut-off state, and C5 is full of; The step-down testing circuit of being made up of triode T2, resistance R 4～R6, capacitor C 9 and diode D1 4 then is in the T2 saturation condition.When the incoming call ring, the ringing voltage that is higher than 60 volts makes the T6 emitter junction obtain to be higher than 0.6 volt voltage turn-on by divider resistance R11 after the B1 rectification, and C5 discharges and by resistance R 13 the reset terminal 9 pin step-downs of single-chip microcomputer resetted.Perhaps, when indoor or outdoor receiver off-book, the output voltage of outside line IN and polarity transformation circuits B1 drop to below 30 volts, make T2 detect voltage landing and end, R6 is after certain anti-interference time of C9 charging time-delay, be added to the base stage of T6 by D4, make the T6 conducting, finish resetting of single-chip microcomputer.Single-chip microcomputer resets after the work, the 2 pin output high level of single-chip microcomputer, reset circuit can not be worked again, and 1 pin output high level by diode D2 the resetting pin clamper of single-chip microcomputer at high level, thereby prevent that misoperation from resetting, pass through then by B2, R15～R16, D4～D5, whether the off-hook detection circuit 2 that 12 pin of photoelectrical coupler O1 and IC2 are formed detects indoor receiver off-book, if not, pass through again by resistance R 17～R18, the electric bell that comes that 11 pin of single-chip microcomputer are formed is pressed zero cross detection circuit 9, can judge whether the ring of sending a telegram here, if be not, promptly be the outside line free call on sb. else's expense through illegal means,, control the base stage of T1 by R3 then by the interference signal of 17 pin output certain frequency, export interference signal by resistance R 1 to circuit by the T1 collector electrode, limit the dialing of outdoor free call on sb. else's expense through illegal means phone.If user's off-hook is then given the T5 base stage that is connected into emitter follower by 18 pin output high level, the T5 conducting, the emitter output current is given double-tone decoding circuit IC1 work frequently, to detect user's dual-tone dialing number; If the user adopts pulse dialing, then by the off-hook detection circuit, by the 12 pin detection pulse dialing of IC2.Detected indoor phone dialed number, by with single-chip microcomputer in the restriction number set of the user that remembers relatively, if the restriction number, then dialing and the conversation by 17 pin and T1 output interference signal limited subscriber phone back.And if send a telegram here ring, then single-chip microcomputer does not remake any work, directly enters sleep state.When single-chip microcomputer detects outdoor phone or indoor phone on-hook, or behind the legal dialing normal talking of indoor phone, also enter sleep state.When single-chip microcomputer entered sleep state, 1,2 and 18 pin elder generations output low level was removed the clamper of reset circuit and is disconnected the power supply of IC1, so that can reset work when indoor, outdoor receiver off-book next time and incoming call ring.

The utility model compared with prior art has following advantage: can limit the pulse of outdoor phone fully with two Voice-frequency dialing, and take full advantage of the intelligent control ability of single-chip microcomputer and produce the outdoor phone of restriction by single-chip microcomputer and dial Number interfering signal, thereby have reliable in function, circuit advantages of simple, advantage that cost is low. Can be used on outside the needs The occasion that the antitheft and indoor phone of line locks.

Claims (4)

1. phone anti-theft puzzle lock, comprise polarity transformation circuits 1, off-hook detection circuit 2, power supply stabilization circuit 3, double-tone is decoding circuit 6 frequently, disturb output circuit 7, single-chip microcomputer 8 etc., it is characterized in that: adopt the step-down testing circuit of forming by triode and peripheral cell thereof 4 to cooperate the incoming call ring reset circuit of forming by triode and peripheral cell thereof 5, and cooperate by cross-over connection in phone inlet wire one end and input pin of single-chip microcomputer, the electric bell that comes that two resistance between the phone inlet wire other end and the reversal output negative pole are formed is pressed zero cross detection circuit 9, directly produces interference signal by single-chip microcomputer and limits outdoor dialing by disturbing output circuit.

2. phone anti-theft puzzle lock according to claim 1, it is characterized in that: in the step-down testing circuit 4, divider resistance R4 one termination reversal output cathode, an end is connected with R5, transistor base, the R5 other end with triode T2 emitter, promptly " " (common port) link to each other; Triode T2 collector electrode connects power supply by resistance R 6, and collector electrode also links to each other with the end of C9, the positive pole of diode D1, another termination of C9 " ", the negative pole of diode D1 connects the base stage of the triode T6 of reset circuit 5.

3. phone anti-theft puzzle lock according to claim 1, it is characterized in that: in the incoming call ring reset circuit 5, divider resistance R11 one end links to each other with the reversal output cathode, the other end and resistance R 12, triode T6 base stage links to each other, R12 one termination triode T6 emitter, triode T6 collector electrode is by the positive pole of resistance R 13 with diode D3, reset terminal 4 pin of resistance R 14 1 ends and single-chip microcomputer link to each other, collector electrode also links to each other with electric capacity one end, the electric capacity other end links to each other with emitter, emitter links to each other with output pin 2 pin of single-chip microcomputer, one end of the negative pole of diode D3 and resistance R 14 links to each other with power supply, another output pin 1 pin that the positive pole of diode D2 connects single-chip microcomputer links to each other, and negative pole links to each other with resetting pin 4 pin.

4. phone anti-theft puzzle lock according to claim 1, it is characterized in that: come electric bell to press in the zero cross detection circuit 9, a resistance cross-over connection is arranged between phone inlet wire one end and polarity transformation circuits negative pole, input pin of single-chip microcomputer is by the answer the call other end of inlet wire of a resistance.

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