CN2090553U

CN2090553U - Theft-proof alarm device

Info

Publication number: CN2090553U
Application number: CN 91209528
Authority: CN
Inventors: 宋彦国
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-06-03
Filing date: 1991-06-03
Publication date: 1991-12-11

Abstract

The utility model relates to a theft-proof alarm, whose power supply is connected with a sound-light alarm device by a theft-proof device, wherein, the anti-theft device comprises a theft-proof switch, and a theft-proof circuit which is composed of electric bridges; the sound-light alarm device comprises an oscillators, and a light alarm circuit and a sound alarm circuit which are connected with the oscillator. The light alarm of the utility model adopts red and green signal lamps to flickeringly alarm, and the sound alarm simulates the sound of police cars. The utility model has the advantages of big output power, less power consumption, and low cost, having the application to families, storehouse, etc.

Description

Theft-proof alarm device

The utility model relates to a kind of electronic anti-theft alarm of guarding against door and window, article box etc.

Existing alarm kind is more, but mostly has deficiency in various degree.Adopt computer and radio transmitting apparatus, though advantage is more, the circuit complexity, cost is higher, and power consumption is bigger when using; Warning device with the door lock logotype is arranged, but must close alarm switch before using, otherwise warning device can not be differentiated owner and criminal, as long as open the door just warning.

The purpose of this utility model is to avoid above-mentioned weak point of the prior art, and provides a kind of warning output power big, and power consumption is little, anti-wrong report, tamper-proof, with low cost burglar alarm.

The purpose of this utility model can reach by following measure:

A kind of burglar alarm comprises power supply 1, anti-theft device and acoustic-optic alarm, and its special character is:

1) described anti-theft device comprises anti-theft switch 2 and the anti-theft circuit of being made up of K switch 1, K2 3, described anti-theft circuit 3 comprises the electric bridge of being made up of resistance R 1～R4, compound circuit, triode BG1～BG2, diode D that triode BG3～BG4 forms, described K switch 2 is in parallel with resistance R 2, and K switch 1 is connected with resistance R 2;

2) described acoustic-optic alarm comprises optical alarm circuit 4,6 and the sound alarm circuit 7 that joins with oscillator 5, and described sound alarm circuit 7 is made up of triode BG11～BG12, capacitor C 3～C5 and loudspeaker L.

Oscillator 5 of the present utility model comprises the positive-feedback circuit of two groups of R-C couplings being made up of triode BG7～BG8, capacitor C 1～C2 and resistance R 5～R8.

Optical alarm circuit 4 of the present utility model comprises compound circuit and the pilot lamp H1 that is made up of triode BG5～BG6, and described optical alarm circuit 6 comprises compound circuit and the pilot lamp H2 that is made up of triode BG9～BG10.

Accompanying drawing drawing of the present utility model is described as follows:

Accompanying drawing is the circuit theory diagrams of the utility model embodiment.

Below in conjunction with accompanying drawing the utility model is further described:

Referring to accompanying drawing, anti-theft device is made up of anti-theft switch 2 and anti-theft circuit 3, and anti-theft circuit 3 is formed electric bridge by resistance R 1～R4, and anti-theft switch adopts microswitch, and K switch 1 is that normally closed contact is connected with resistance R 2, and K switch 2 is a normal opened contact, and is in parallel with resistance R 2.Adjust the resistance of resistance R 1,2 current potentials of A, B are equated, then under the normal condition, the base stage of triode BG1, BG2, the emitter current potential equates that electric bridge is in equilibrium state, triode BG1, not conducting of BG2, diode D and triode BG3, the also not conducting of BG4 compound circuit, the not conducting of whole warning circuit is on the alert.Acoustic-optic alarm is made up of sound alarm circuit 7, oscillator 5 and optical alarm circuit 4,6.The multivibrator that oscillator 5 is made up of the positive-feedback circuit of a two-stage R-C coupling, the output signal of triode BG7 collector is coupled to the base stage of triode BG8 through capacitor C 2, the collector output signal of triode BG8 is coupled to the base stage of triode BG7 again through capacitor C 1, because the output signal and the input signal of common emitter circuit are anti-phase, then the cross-couplings of this two-stage constitutes the closed circuit with positive feedback effect.Because during multivibrator 5 work that triode BG7, BG8 form is that one of a conducting ends, hocket, so, being connected on also alternate conduction or end of triode BG5～6 of triode BG7 and BG8 collector output and BG9～10 respectively, pilot lamp H1 and H2 correspondingly glimmer.Two pilot lamp can adopt the color lamp of red green two color, and alternately flicker is with noticeable.The acoustic alarm device that acoustic alarm device 7 is made up of triode BG11, BG12 complementary circuit, signal after triode BG12 amplifies feeds back to triode BG11 through capacitor C 4, resistance R 10 again and forms audio oscillator signal, this audio oscillator signal is subjected to the pulse signal modulation of oscillator 5, change the resistance of resistance R 9, can change oscillation frequency and output power.Capacitor C 1 in the oscillator 5, C2 adopt two capacitors that capacity is different, can make alarm produce " liter ", " falling " accent.Increase the value of capacitor C 1, the quiescent interval increases, and increases the value of capacitor C 2, and increase the perdurability that then modifies tone.The big I of the value of capacitor C 3 influences the modified tone cycle, and capacitor C 3 values reduce, and the cycle accelerates.During the utility model work, if normally closed switch K1 is disconnected, then A point current potential raises, B point current potential is constant, triode BG1 conducting, diode D conducting, triode BG3, BG4 at this moment, had both made the K1 that closes a switch because of also conducting of bias current is arranged, triode BG3, BG4 will continue conducting, the driving acoustic-optic alarm is reported to the police, and promptly pilot lamp H1, H2 send blinking light, and loudspeaker L sends simulation police car chimes of doom, at this moment, have only power cutoff 1 could eliminate warning.When normal open switch K2 was closed, A point current potential was about zero volt, and triode BG2 has forward bias and conducting, and sound and light alarm is carried out in acoustic-optic alarm work.When K switch 1, K2 are opened a way or during short circuit, acoustic-optic alarm still sends alerting signal simultaneously.

Triode BG1, the BG2 of present embodiment can adopt the triode of β 〉=100 of 3DG6 or 3DG series; Triode BG3, BG4 can adopt the triode of 3AX31 or other 3AX series β 〉=40, and triode BG7, BG8 can adopt the triode of β＞40 such as 3AX8,3AX22, and triode BG12 can adopt 3AX81 or 3AX61, the pipe of β＞80.Power supply can adopt the dry cell of 1.5 volts at 6 joints.Also available two the NE555 time base circuits of the circuit of the utility model acoustic-optic alarm replace.The utility model can be guarded against a plurality of door and windows and article simultaneously, for example on balcony arranges a finer wire, and it is connected with K switch 1, can guard against balcony door.Be arranged under the table top of valuables box with a tongue tube normally closed or that often open, with the lead-in wire of tongue tube serial connection or be attempted by K switch 1 or K2 goes up and gets final product.

The utility model is compared with existing technology has following advantage:

1, the utility model can be guarded against in 24 hours at any time, and power consumption is little.

2, the anti-newspaper property of separating is strong, opens circuit, short circuit all can report to the police, and the normal switch door lock can not produce false alarm.

3, power output is big, and simulation police car sound and traffic lights alternately flicker are reported to the police, and are easily noticeable.

4, volume is little, and is with low cost, each about 20 yuan.

Claims

1, a kind of burglar alarm comprises power supply 1, anti-theft device and acoustic-optic alarm, it is characterized in that:

1) described anti-theft device comprises anti-theft switch 2 and the anti-theft circuit of being made up of K switch 1, K2 3, described anti-theft circuit 3 comprises the electric bridge of being made up of resistance R 1～R4, compound circuit, triode BG1～BG2, the diode D that triode BG3～BG4 forms, described K switch 2 is in parallel with resistance R 2, and K switch 1 is connected with resistance R 2;

2, burglar alarm according to claim 1 is characterized in that: described oscillator 5 comprises the positive-feedback circuit of two groups of R-C couplings being made up of triode BG7～BG8, capacitor C 1～C2 and resistance R 5～R8.

3, burglar alarm according to claim 1 and 2, it is characterized in that: described optical alarm circuit 4 comprises compound circuit and the pilot lamp H1 that is made up of triode BG5～BG6, and described optical alarm circuit 6 comprises H2 such as the compound circuit be made up of triode BG9～BG10 and indication.