CN2279037Y

CN2279037Y - Telephone line alarm device adapted for all-model telephones for preventing fraudulent calling

Info

Publication number: CN2279037Y
Application number: CN 95221068
Authority: CN
Inventors: 甘美金
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-09-07
Filing date: 1995-09-07
Publication date: 1998-04-15
Anticipated expiration: 2005-09-07

Abstract

The utility model relates to a telephone safety device, particularly an anti-theft alarm device for all-type telephones and telephone lines, composed of a detecting circuit, an executive circuit, an alarm circuit and a power supply. The utility model is characterized in that no matter what types of telephone sets thieves use for stealing, the anti-theft alarm device can prevent the thieves dialing signals and alarm, and also send out alarms when the lines are cut off.

Description

Full type telephone line burglar alarm

The utility model relates to a kind of phone protective device, particularly a kind of full type telephone line burglar alarm.

Phone is by free call on sb. else's expense through illegal means, refers to robber person here and calls and the behavior that allows normal users on this circuit pay at extension telephone machine on others' telephone line (hereinafter to be referred as robber's machine).This type of device that occurs on the market at present is because what adopt is that the mode of audio disturbances is disturbed the dialing of robber's machine, so the big and wide pulse signal of transfering when paired pulses dial telephone set and old-fashioned pulse machine are made robber's machine of amplitude does not have interference effect, thereby loses anti-theft feature.

The purpose of this utility model is to provide a kind of signal of transfering when all phone types are made robber's machine can both play effective inhibiting telephone line burglar alarm.

The utility model is made up of testing circuit (A), executive circuit (B), alarm circuit (C) and power supply (F).In testing circuit (A), telephone line-utmost point feeder line " link " end-extremely be connected with ground, resistance R 4 is serially connected in+polar curve on, one end is connected with telephone set by " machine of answering the call " end, the other end be connected with the voltage-stabiliser tube D-utmost point and by " link " hold+extremely insert telephone line+utmost point feeder line, voltage-stabiliser tube D+utmost point and resistance R 1, R2 polyphone back ground connection, the contact of resistance R 1, R2 connects triode VT1 base stage, its grounded emitter, collector series connection resistance R 3 backs are connected with the battery E+ utmost point.Voltage-stabiliser tube D-input of testing circuit (A) very, the current collection of triode VT1 is the output of testing circuit (A) very.When normal users was made a phone call, switch produced a pressure drop to the electric current (voltage) that telephone set provides through resistance R 4 and on resistance R 4; And robber's machine is on the telephone line that connects " link " end when making a phone call, and the electric current that switch provides to robber's machine (voltage) is without resistance R 4, so do not have pressure drop on the resistance R 4.Testing circuit (A) judges that to have or not pressure drop on the resistance R 4 telephone line has or not stolen phenomenon.In executive circuit (B), the grounded emitter of triode VT2, base stage connect triode VT1 current collection level, resistance R 3 and capacitor C 1+level, capacitor C 1-utmost point ground connection.Triode VT2 collector electrode is connected with triode VT3 base stage, triode VT2 and VT3 constitute the reversed polarity compound transistor, triode VT3 emitter connects the battery E+ utmost point, ground connection behind its collector series relay JR, the moving contact ground connection of relay J R, its normally-closed contact K2 is the control end of warning circuit (C), its normally opened contact K1 and capacitor C 2-utmost point is connected, capacitor C 2+utmost point by " wiring terminal "+extremely with telephone line+utmost point feeder line is connected.The base stage of triode VT2 is the input of executive circuit (B).Executive circuit (B) is controlled by testing circuit (A).When the crime of robber's machine is arranged on the circuit, executive circuit (B) action, relay J R adhesive, its normally opened contact K1 closure, with capacitor C 2 with the form short circuit of pure capacitive reactance in+, between-two phone feeder lines, filter the signal that robber's machine is transfered, when capacitor C 2 is got enough big value with the form of ac short circuit, just can filter any type and make the signal that robber's machine is transfered, to reach the antitheft purpose of the utility model.Warning circuit (C) is the self-oscillation warning circuit.In warning circuit (C), triode VT4 grounded emitter, base stage is connected with the normally-closed contact K2 of resistance R 5, capacitor C 3 and relay J R, its collector electrode is connected with triode VT5 base stage, resistance R 5 connects the battery E+ utmost point, the other end of capacitor C 3 is connected with the collector electrode of triode VT5, the end of buzzer Y, the other end ground connection of buzzer Y, and the emitter of triode VT5 connects battery E+ level.When on the circuit during crime of no robber's machine, not adhesive of relay J R, its normally-closed contact K2 is the base stage shorted to earth of triode VT4, and warning circuit (C) can't starting of oscillation, and buzzer Y is noiseless; Otherwise, when the crime of robber's machine is arranged on the circuit, relay J R adhesive, its normally-closed contact K2 disconnects, and triode VT4 base stage obtains normal current potential, warning circuit (C) starting of oscillation, buzzer Y sends chimes of doom.Power supply (F) is made of separately battery E, battery E+level and the emitter of triode VT3, YT5 and resistance R 3, R5 be connected, battery E-utmost point ground connection.

In executive circuit (B), triode VT2 is the NPN type, and triode VT3 is a positive-negative-positive; The collector electrode of triode VT2 and triode VT3 base stage connect and compose compound transistor, the grounded emitter of triode VT2, base stage is connected with the collector electrode of triode VT1, connect capacitor C 1 between this contact and the ground, triode VT3 emitting stage connects battery E+ level, ground connection behind the collector series relay JR, the normally-closed contact K2 of relay J R is connected with an end of three utmost point VT4 base stages, resistance R 5, capacitor C 3, its normally opened contact K1 is connected with the capacitor C 2-utmost point, its moving contact ground connection, capacitor C 2+the utmost point circuit+utmost point feeder line of answering the call; When no robber's machine or normal users were made a phone call on the circuit, triode VT1 current collection is electronegative potential very, not adhesive of relay J R.The capacitor C 2 that is connected on its normally opened contact K1 is unsettled fully, so switch and normal users telephone set are had no effect, its normally-closed contact K2 is with the base stage shorted to earth of triode VT4 simultaneously, and warning circuit (C) is not worked; When the crime of robber's machine is arranged on the circuit, triode VT1 current collection is high potential very, compound transistor VT2, the VT3 conducting, relay J R adhesive, its normally-closed contact K2 disconnects, warning circuit (C) starting of oscillation, send chimes of doom, its normally opened contact K1 closure, with capacitor C 2 short circuits between two phone feeder lines, robber's machine is carried out ac short circuit, since adopted with relay J R only on telephone line, have robber's machine when crime ability with capacitor C 2 with the form short circuit of pure capacitive reactance in+, technical scheme between-two phone feeder lines, thus enough big value C2 can be got, the utility model can be fallen the target signal filter that the various model robber's machines that comprise the pulse dialing telephone machine are transfered, overcome paired pulses dialing signal in the prior art and can't cause and to disturb and lose the shortcoming of anti-theft feature, do not influenced the operate as normal of telephone subscriber and switch again.

Line map of the present utility model is provided by accompanying drawing.

The described the utility model of accompanying drawing is made up of testing circuit (A), executive circuit (B), warning circuit (C) and power supply (F) four parts, and four part with dashed lines separate signal." machine of answering the call " of the present utility model end is connected with two feeder lines of telephone set, " link " end+extreme and telephone line+utmost point feeder line is connected, its-extremely be connected with ground and with telephone line-utmost point feeder line is connected.Triode VT1, VT2, VT4 are the NPN type, and triode VT3, VT5 are positive-negative-positive.

In testing circuit (A), resistance R 4 is serially connected in+polar curve on, one end is connected with telephone set by " machine of answering the call " end, the other end be connected with the voltage-stabiliser tube D-utmost point and by " link " end and telephone line+utmost point feeder line is connected, voltage-stabiliser tube D+utmost point and resistance R 1, R2 polyphone back be by R2 ground connection, the base stage of triode VT1 is connected with the contact of resistance R 1, R2, and its grounded emitter connects the battery E+ utmost point after the collector series connection resistance R 3.In executive circuit (B), the grounded emitter of triode VT2, the collector electrode of base stage and triode VT1 and capacitor C 1+utmost point is connected, the collector electrode of triode VT2 is connected with the base stage of triode VT3, capacitor C 1-utmost point ground connection, the emitter of triode VT3 connects the battery E+ utmost point, ground connection behind its collector series relay JR, the moving contact ground connection of relay J R, its normally opened contact K1 is connected with the capacitor C 2-utmost point.Its normally-closed contact K2 is the control end of warning circuit (C), the capacitor C 2+ utmost point circuit+utmost point feeder line of answering the call.In warning circuit (C), triode VT4 grounded emitter, base stage is connected with the normally-closed contact K2 of resistance R 5, capacitor C 3 and relay J R, collector electrode is connected with the base stage of triode VT5, the other end of resistance R 5 is connected with the emitter and the battery E+ utmost point of triode VT5, capacitor C 3 is connected the other end ground connection of buzzer Y with the current collection level of triode VT5, the end of buzzer Y.Power supply (F) is made of separately battery E, battery E-utmost point ground connection ,+the utmost point is connected with emitter, resistance R 3, the R5 of triode VT3, VT5.

In preferred embodiment of the utility model, when capacitor C 2 is got 220～330 microfarads, can filter the signal that various type robber machines are transfered completely; Voltage-stabiliser tube D gets 12V, and resistance R 4 is got 560 Ω, R1 and got 100K Ω, and R2 gets 10K Ω can make the switch online reliably working of the utility model at 24～60V feed voltage voltage; Resistance R 3 is got 200K Ω, and R5 gets 470K Ω, under the situation of no robber's machine crime, can make battery E use more than 1 year.

The utility model is work like this:

The utility model is connected " answer the call machine " termination normal users telephone set in the mode of "+connect+", " connecing-" with " link " end by the polarity of telephone line feed voltage.

When no robber's machine crime on the circuit, when normal users is not made a phone call yet, 24～60V feed voltage voltage punctures voltage-stabiliser tube D, again through resistance R 1, R2 dividing potential drop, make triode VT1 conducting, because resistance R 3 values are bigger, this conducting is a saturation conduction, its current collection is electronegative potential very, this electronegative potential is being clamped down on the base potential of triode VT2, to compound transistor VT2, VT3 are ended, and not adhesive of relay J R; The capacitor C 2 that is connected on its normally opened contact K1 is unsettled fully, and its normally-closed contact K2 is with the base stage shorted to earth of triode VT4, and warning circuit (C) loses starting condition for oscillation and not starting of oscillation, and buzzer Y is noiseless, and the utility model is in static state.

When normal users is called, switch provides operating current (voltage) by resistance R 4 to telephone set, this electric current causes pressure drop on resistance R 4, the operating voltage of this pressure drop and telephone set is (after 7～8V) additions, still greater than the puncture voltage of voltage-stabiliser tube D, so voltage-stabiliser tube D is still breakdown, this voltage still can make triode VT1 saturation conduction again after resistance R 1, R2 dividing potential drop, its collector electrode still is an electronegative potential, compound transistor VT2, VT3 still end, not adhesive of relay J R, the utility model still are in static state.

When the crime of robber's machine is arranged on the circuit, the electric current that switch provides to robber's machine (voltage) is without resistance R 4, so do not have pressure drop on the resistance R 4, at this moment, the voltage that the operating voltage of robber's machine, the feed voltage on the circuit and voltage-stabiliser tube D-extremely go up equates, be 7-8V, this voltage is less than the puncture voltage of voltage-stabiliser tube D, so voltage-stabiliser tube D ends.Resistance R 1, R2 and the equal no-voltage of triode VT1 base stage, so triode VT1 also ends, its collector electrode becomes high potential, at this moment, 3 one-tenth of resistance R the biasing resistor of compound transistor VT2, VT3, make its conducting, relay J R adhesive, its normally-closed contact K2 disconnects, and makes triode VT4 base stage obtain normal current potential, warning circuit (C) starting of oscillation, buzzer Y sends chimes of doom; Simultaneously, the normally opened contact K1 closure of relay J R between two phone feeder lines, is carried out ac short circuit to stealing the machine signal with capacitor C 2 short circuits, robber's machine can't be worked, to realize the purpose of this utility model.

When robber person cuts off telephone wire when (containing line short), the equal dead electricity of base stage of voltage-stabiliser tube D, resistance R 1, R2 and triode VT1, with above-mentioned reason when the crime of robber's machine is arranged, buzzer Y also can send chimes of doom, so the utility model has the telephone line fault alarm function concurrently.

Claims

A kind of when only on telephone line, illegally being connected to telephone set (hereinafter to be referred as robber's machine) free call on somebody else's expense through illegal means with relay J R just with capacitor C2 short circuit between two phone feeder lines to carry out the full type telephone line burglar alarm of ac short circuit to stealing the machine signal; Form by power supply (F), warning circuit (C), testing circuit (A) and executive circuit (B); Power supply (F) is made of separately battery E, its-utmost point ground connection; Warning circuit (C) is the self-oscillation warning circuit, wherein, triode VT4 is the NPN type, triode VT5 is a positive-negative-positive, and triode VT4 base stage is connected its grounded emitter with the normally-closed contact K2 that resistance R 5, capacitor C 3 and relay are held JR, collector electrode is connected with the base stage of triode VT5, the other end of the emitter connecting resistance R5 of triode VT5 also is connected with the battery E+ utmost point, and its collector electrode is connected the other end ground connection of buzzer Y with the other end of capacitor C 3 and the end of buzzer Y; In testing circuit (A), triode VT1 pipe is the NPN type, and resistance R 4 is serially connected on telephone line+utmost point feeder line, and an end is connected with the normal users telephone set by the machine end of answering the call, another termination voltage-stabiliser tube D-utmost point, and by wiring terminal+extremely be connected with telephone line+utmost point feeder line; Voltage-stabiliser tube D+ level and resistance R 1, R2 polyphone back are by resistance R 2 ground connection, the contact of resistance R 1, R2 connects the base stage of triode VT1, its grounded emitter, connect the battery E+ utmost point after its collector series connection resistance R 3, testing circuit (A) has or not the crime of robber's machine in order to detect on the telephone line, detection signal is exported by triode VT1 collector electrode; It is characterized in that: in executive circuit (B), triode VT2 is the NPN type, and triode VT3 is a positive-negative-positive; The collector electrode of triode VT2 and triode VT3 base stage connect and compose compound transistor, the grounded emitter of triode VT2, base stage is connected with the collector electrode of triode VT1, connect capacitor C 1 between this contact and the ground, triode VT3 emitter connects the battery E+ utmost point, ground connection behind the collector series relay JR, the normally-closed contact K2 of relay J R is connected with an end of triode VT4 base stage, resistance R 5, capacitor C 3, its normally opened contact K1 is connected with the capacitor C 2-utmost point, its moving contact ground connection, capacitor C 2+the utmost point circuit+utmost point feeder line of answering the call; When no robber's machine or normal users are made a phone call on the circuit, triode VT1 current collection is electronegative potential very, not adhesive of relay J R, the capacitor C 2 that is connected on its normally opened contact K1 is unsettled fully, so switch and normal users telephone set are had no effect, its normally-closed contact K2 is with the base stage shorted to earth of triode VT4 simultaneously, and warning circuit (C) is not worked; When the crime of robber's machine was arranged on the circuit, triode VT1 current collection is high potential very, compound transistor VT2, VT3 conducting, relay J R adhesive, its normally-closed contact K2 disconnects, and chimes of doom is sent in warning circuit (C) starting of oscillation, its normally opened contact K1 closure, with capacitor C 2 with pure capacitive reactance state short circuit between two phone feeder lines, carry out ac short circuit to stealing the machine signal, when C2 gets 220～330 microfarads, be enough to filter any type and make the signal that robber's machine is transfered, but the work of switch is not had influence.