CN2065344U

CN2065344U - Burglar alarm

Info

Publication number: CN2065344U
Application number: CN 90206187
Authority: CN
Inventors: 陈德荣
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-05-14
Filing date: 1990-05-14
Publication date: 1990-11-07

Abstract

The utility model discloses a burglar alarm, which judges the owner by the preset unlocking time range. When the unlocking time range exceeds the preset time, the burglar alarm sends out alarm. The utility model is composed of an induction terminal, a trigger circuit, a switch circuit, a sound generator, a power amplifier, a loudspeaker, a starting timing circuit, a stopping timing circuit, etc.

Description

Burglar alarm

The utility model relates to a kind of burglar alarm, and it is applicable to that warehouse, shop, family etc. need the department of taking precautions against, and belong to the warning device class.

At present, developed the guard against theft and alarm system that some have recognition function in the world.As fingerprint recognition, voice recognition or the like, but these warning systems all exist and cost an arm and a leg, the weakness that complex structure is difficult for promoting the use of, general warning system, it is only just can send alerting signal at burglar's sled when pounding door and window or twisting into two parts power lead as disclosed a kind of " burglar alarm " among the Chinese patent CN86209122, burglar's crime means of now is more and more hidden, they can turn the key in the lock as owner, or use the thing of similar key easily door lock to be disclosed out, and do not make other sound, make that like this warning device is malfunctioning.

For overcoming above-mentioned deficiency, the purpose of this utility model provides a kind of burglar alarm of differentiating true and false owner in the given time.

For achieving the above object, the utility model has adopted following design proposal: make trigger circuit upsets, open on-off circuit and make then to start timing circuit and stop timing circuit and pick up counting by the induction terminal, the timing time that starts timing circuit is owner and estimates to unblank required time (generally within tens seconds), owner during this period of time unblanks to enter, press reset button, whole warning device recovers the state of alert, waits for and unblanking next time; When burglar's attempt is unblanked, even do not surpass the schedule time or open door lock in the given time because key is not split the key time, owing to do not know to press reset button, starting the timing circuit timing time arrives, make second group of trigger circuit upset, second group of on-off circuit is opened, and makes alarm send police whistle sound then, arrive until stopping the timing circuit timing time, siren stops.The utility model is by induction terminal, luminous indicating circuit, two groups of trigger circuit, two groups of on-off circuits, start timing circuit, stop the circuit of timing, reset button and sound generator, power amplifier, loudspeaker etc. are partly formed, and are provided with the double loop power supply electric supply installation.

The utility model reliable operation, disguised strong, criminal is difficult to escape this device.This apparatus structure is simple, little power consumption, and cost is low, is easy to promote the use of.

Below in conjunction with accompanying drawing the utility model is done to describe further:

Fig. 1 is the theory diagram of burglar alarm.

Fig. 2 is the circuit theory diagrams of burglar alarm.

Fig. 3 is a kind of appearance assumption diagram of burglar alarm.

As shown in Figure 1, the utility model is by induction terminal 1, luminous indicating circuit 3, trigger circuit 2 and trigger circuit 6, on-off circuit 4 and on-off circuit 7, start timing circuit 5, stop timing circuit 11, reset button 12 and sound generator 8, power amplifier 9, loudspeaker 10 etc. are partly formed.As shown in Figure 2, induction terminal 1 can be with shielding line or bifilar parallel lines, two groups of trigger circuit 2 and 6 can be made of integrated 16 of a NE556, on-off circuit 4 can be made of triode 19,20 and biasing resistor, on-off circuit 7 can be made of triode 23,24 and biasing resistor, sound generator can be made of integrated 8 of KD-9561, and starting timing circuit 5 can be made of resistance 21 and electric capacity 22, and stopping timing circuit can being made of resistance 17 and electric capacity 18.Power amplifier 9 can be made of TWH 8778 high power switch integrated circuit, the course of work of entire circuit is such, when induction terminal 1 is sensed human body signal, trigger circuit 2 output high level, make luminous indicating circuit luminous, make and stop timing circuit and pick up counting, be that supply voltage passes through resistance 17 to electric capacity 18 chargings, make triode 19 conductings simultaneously, along with triode 19 conductings, triode 20 end, the startup timing circuit is picked up counting, and promptly electric capacity 22 is by resistance 21 chargings; Current potential reduces the low triggering end of trigger circuit 6 along with electric capacity 22 chargings, when current potential drops to 2/3 supply voltage, promptly starting timing time arrives, trigger circuit 6 output high level, make triode 23,24 conductings, sound generator 8 is started working, and produces the siren signal, exports to power amplifier 9 and amplifies back promotion loudspeaker 10 sounding.In electric capacity 18 charging processes, the high-triggering end current potential of trigger circuit 2 rises gradually, when current potential rises to 2/3 supply voltage, promptly stopping timing time arriving, perhaps when having pressed reset button, make trigger circuit 2 output low levels, triode 19 ends, triode 20 conductings, the low triggering end of trigger 6 is a high level, trigger circuit 6 output low levels are ended triode 23,24, and sound generator 8 quits work, no siren signal produces, and loudspeaker 10 is sounding not.In actual applications, induction terminal 1 can be received on the door lock energized latch 26, click reset switch 12, owner's spring lock of going out, hand does not bump door lock again, when returning, turn the key in the lock enter house after, press reset button 12 or pull out power plug 26 and get final product, when the criminal want to open the door lock with screwdriver, false key, steel wire etc., its time of opening the door was difficult to be controlled within tens seconds, even the criminal really enters the room in the given time, also be difficult to stop alarm to be sent.This device also is provided with double loop power supply power supply, and promptly a Battery pack 25 is connected with the normally closed contact 27 of relay afterwards as the standby power supply of whole device, and electric network source switch 28 is with after relay input end coil 29 is connected, and is in parallel with the battery branch road.In the ordinary course of things, the latch 26 closed electric network source switches 28 that plug in, normally closed contact 27 disconnects, and battery is not powered, and this installs by mains supply, if after criminal enters house, cuts off and drives this power lead, normally closed contact 27 adhesives, powered battery, this installs still operate as normal.As shown in Figure 3, for this installs a kind of surface structure synoptic diagram, luminous indication 3 is housed on shell 15, reset button 12, power plug 26, electric network source switch 28 and loudspeaker 10.

Claims

1, a kind of burglar alarm, be by induction terminal 1, send indication 3, trigger circuit, on-off circuit, sound generator 8, power amplifier 9, loudspeaker 10 and power supply etc. and partly form, it is characterized in that it also comprises startup timing circuit 5 and stops timing circuit 11.

2, burglar alarm according to claim 1 is characterized in that it also can comprise a reset button 12.

3, burglar alarm according to claim 1 is connected across the standby power supply of entire circuit input end as this device after it is characterized in that having a Battery pack 25 and the normally closed contact 27 of relay being connected; It is in parallel after electric network source switch 28 is connected with relay input end coil 29 with the battery branch road.