CN2124456U - Theftproof alarm device - Google Patents

Abstract

The utility model relates to a holding theftproof alarm device which is composed of a monitor and an alarm. The holding theftproof alarm device is characterized in that the monitor adopts a capacitance three-point oscillation circuit to generate a high frequency modulation signal which is emitted by an antenna; the alarm adopts a regenerative reception circuit; the antenna is used for receiving the high frequency signal; a vocalization circuit sounds and gives an alarm; the holding theftproof alarm device is also provided with a scrambler which is composed of a code written switch and an encoder. The monitor of the utility model is carried by a person who holds an article. The alarm is arranged in the article which is held. When the article is a certain distance away from the person who holds the article, the holding theftproof alarm device can automatically give an alarm.

Description

Theftproof alarm device

The utility model relates to burglar alarm, more particularly, is that a kind of person that is particularly useful for holding the thing is to its device that object carries out burglar alarm of holding.

Of the prior art to hold the thing burglar alarm of a great variety, but all be to detect by being fixed on robber's feelings probe on a certain particular location of object (as touch switch etc.) mostly.In a single day this structure is grasped by stealer, just can control by it, thereby make alarm lose its due effect.Also there is not a kind of effective thing burglar alarm of holding at present.

The purpose of this utility model is to avoid the deficiencies in the prior art part, and a kind of thing burglar alarm of holding simply, reliably is provided, and is left the certain distance of person of holding the thing in case hold object, can send sharp-pointed chimes of doom.

The purpose of this utility model is achieved through the following technical solutions.

The utility model is made of watch-dog and alarm.Described alarm constitutes the sounding loop by warning tablet, power tube and loudspeaker.

Of the present utility model being characterised in that:

A, described watch-dog constitute the capacitance three-point type oscillation circuit by triode, inductance and capacity cell, and the high-frequency modulation signal of output is connected to emitting antenna by electric capacity.

B, described alarm constitute the regenerative reception loop by receiving antenna, electric capacity, inductance and triode, and the output of receiving loop is through inductance, capacitor filtering demodulation, and are amplified to the sounding loop by the operational amplifier shaping.

Feature of the present utility model also is, is provided with respectively in described watch-dog and alarm by making the scrambler that code switch and scrambler constitute.

The person carries watch-dog of the present utility model by holding the thing, and alarm is arranged in the object.When object leaves the person's certain distance of holding the thing, send alert sound automatically, remind the loser, give lost article rapidly for change.

The utlity model has following advantage:

1, the utility model with watch-dog as microtransmitter, with alarm as receiver, carry high frequency modulation signal therebetween.Its simple in structure, reliable operation.Overcome and held the thing alarm owing to adopting touch switch etc. in the prior art as stealing the defective that the feelings detection probe is easy to be stolen by stealer control.

2, the utility model employing crypto-alarm, and its password can change at any time, has greatly improved confidentiality.

3, the utility model volume is little, alarm sound is big.

4, the utility model alarm distance is adjustable, according to operating distance, can be applicable to different occasions, forms different types of panalarm.Also can be used for the antitheft of bicycle, automobile.

Fig. 1 is the utility model monitor circuit schematic diagram.

Fig. 2 is the utility model alarm circuit schematic diagram.

By the following examples, in conjunction with the accompanying drawings the utility model is further described.

Embodiment:

Referring to Fig. 1, adopt seven and beat code switch DSW ₂With ED5026 scrambler IC ₅By beating code switch DSW ₂With scrambler IC ₅2～8 pin place " 0 " or one state, can form 128 kinds of passwords.If 2187 kinds of passwords are promptly arranged as ternary conversion (i.e. " 0 ", " 1 " and " sky ").If utilize 1 pin,, then there are 16384 kinds as the conversion of 0 attitude.These codings can be selected arbitrarily by the user.Scrambler IC ₅Can export a succession of pulse signal of different in width and dutycycle automatically according to coding.Scrambler IC ₅OVT end line and triode BG ₄Base stage links to each other.Triode BG ₄, inductance L ₃, capacitor C ₁₃, C ₁₄And C ₁₅Constitute the capacitance three-point type oscillation circuit, produce high-frequency modulation signal, pass through capacitor C ₁₇And by emitting antenna n ₂Be transmitted into aerial.

Referring to Fig. 2, identical with watch-dog, adopt seven and beat code switch DSW ₁With ED5027 demoder IC ₃Constitute cryptopart.Demoder IC ₃IN end line and IC ₂Output line links to each other, its VT end line and triode BG ₂Base stage links to each other, BG ₂Collector be connected to warning tablet IC ₄Tablet IC wherein reports to the police ₄, power tube BG ₃Constitute the sounding loop with loudspeaker L.In alarm shown in Figure 2, by receiving antenna n ₁, capacitor C ₂, inductance L ₁With triode BG ₁Constitute the regenerative reception loop.

In the use, at first with DSW ₁Duty and DSW ₂Transfer to identical.Adjust the resonant capacitance C in the receiver again ₂, make receive frequency equate the carrier pulse signal that to receive that transmitter sends with transmission frequency.Signal is through L ₂, C ₆Filtering is through IC ₁Amplify, again through R ₇, C ₃IC is passed through in the integration shaping ₂Amplify, send into the IN pin of ED5027.When the duty of ED5027 and ED5026 was identical, the VT pin of ED5027 had pulse output (if ED5027 is inequality with the duty of ED5026, then pulse-free signal output), the pulse signal trigger triode BG that is exported by the VT pin ₂Work, output low level, the alarm sound sheet is not worked, and does not report to the police.If alarm leaves the watch-dog certain distance, then receiver can not receive the signal that watch-dog is launched, thereby ED5027 is because no input signal, and its output pin VT becomes low level, BG ₂End alarm sound sheet IC ₄Be subjected to noble potential and trigger, and send chimes of doom, through BG ₃Be amplified to loudspeaker L, tell the position at people's object place, reach the purpose of warning.

Claims (2)

1, a kind of thing burglar alarm of holding is made of watch-dog and alarm, and described alarm is by warning tablet IC ₄, power tube BG ₃Constitute the sounding loop with loudspeaker L; It is characterized in that:

A, described watch-dog are by triode BG ₄, inductance L ₃, capacitor C ₁₃, C ₁₄And C ₁₅Constitute the capacitance three-point type oscillation circuit, the high-frequency modulation signal of output passes through capacitor C ₁₇Be connected to emitting antenna n _P

B, described alarm are by receiving antenna n ₁, capacitor C ₂, inductance L ₁With triode BG ₁Constitute the regenerative reception loop; The output of described receiving loop is through L ₂, C ₆Demodulation by filter, and by IC ₁, IC ₂Shaping is amplified to the sounding loop.

2, burglar alarm according to claim 1 is characterized in that, is provided with respectively in described watch-dog and alarm by beating code switch DSW ₂, DSW ₁With scrambler IC ₅, demoder IC ₃The scrambler that constitutes; Described scrambler IC ₅OVT end line and triode BG ₄Base stage links to each other; Described demoder IC ₃IN end line and IC ₂Output line links to each other, its VT end line and triode BG ₂Base stage links to each other, BG ₂Collector is connected to warning tablet IC ₄