CN221804825U - A self-sounding sign signal amplifier circuit based on commodity anti-theft system - Google Patents

The utility model provides a self-ringing sign signal amplifying circuit based on an anti-theft system of commodities, which comprises: the automatic alarm system comprises a control circuit, a label protection circuit, a small signal receiving and amplifying circuit, a power supply circuit and an alarm circuit, wherein the label protection circuit, the small signal receiving and amplifying circuit, the power supply circuit and the alarm circuit are respectively connected with the control circuit, and particularly, the automatic alarm system is characterized in that the signal amplification factor is large, the waveform is not deformed, the power consumption is low, smaller signals can be detected, the conventional signal amplifying circuit adopts an integrated operational amplifier IC to realize small signal amplification, the self-alarm label of the commodity anti-theft system is matched with the commodity anti-theft system for use, and the double protection functions of label alarm and host alarm are realized, and is used for protecting valuable commodities such as sports goods, leather bags, high-grade clothes and the like. When the binding band bound on the commodity is pulled out or sheared off, or the label is peeled off and stuck to the commodity, the label can give out a loud audible and visual alarm, and simultaneously, the host machine can be triggered to give an alarm, so that double protection is realized, and the theft is prevented.

Self-ringing sign signal amplifying circuit based on commodity anti-theft system

Technical Field

The utility model relates to the technical field of commodity burglary prevention, in particular to a self-ringing sign signal amplifying circuit based on a commodity burglary prevention system.

Background

EAS (E lectronic Article Survei l lance ) systems are mainly installed at an open store entrance such as a clothing store, a retail store, etc., where a detection zone is formed in a certain range, and when a non-deactivated tag on an article passes through the detection zone, a detection device detects the tag signal and recognizes the signal, and if the tag signal is a valid tag signal, the device outputs an audible and visual alarm prompt to protect the article. Along with the increasing complexity of the environments of shops and stores, more and more noise sources influence the detection of equipment on tag signals to a great extent, so that the detection distance of the equipment is short, and false alarm and missing report are easy to occur.

Is commonly used for commodity anti-counterfeiting and protection. Such systems typically use a tag signal identification device that detects and identifies a tag signal when an article passes through a detection zone without removal of the tag. If the tag signal is valid, i.e. the tag is present and authentic, the device will output an audible and visual alarm to alert the article to unauthorized or illegal processing.

The integrated operational amplifier IC of the existing self-ringing signage signal amplifying circuit has the problems of high power consumption, high cost and inconvenience for mass production, so that the self-ringing signage signal amplifying circuit based on the commodity anti-theft system is necessary to be realized, the problems of high power consumption and high cost are effectively solved, and a research and development team designs some simple solutions:

Selecting a proper transistor or a field effect transistor: a transistor or a field effect transistor having low power consumption, high amplification factor, and good linearity can be selected as the amplifying device.

And (3) designing a proper amplifying circuit: directly coupled amplification circuits, such as common emitter amplification circuits or common source amplification circuits, may be employed. Such a circuit can maintain the integrity of the input signal while providing high amplification.

And (3) adding a feedback resistor: in order to maintain the stability of the circuit and reduce distortion, a feedback resistor may be added to the amplifying circuit.

Adjusting bias voltage: in order to keep the amplifying circuit stable in a static state, a bias voltage may be added.

Optimizing power management: to reduce power consumption, power management may be optimized. For example using a switching power supply or dynamic power management techniques.

Optimizing wiring: to reduce signal loss and interference, wiring may be optimized. For example, using multilayer boards or surface mount technology.

Selecting proper resistance, capacitance and inductance: in order to improve the performance and stability of the circuit, resistance, capacitance and inductance with high precision and high stability can be selected, and therefore, the self-ringing signage signal amplifying circuit based on the commodity anti-theft system is provided.

Disclosure of utility model

In view of the foregoing, it is desirable to provide a self-sounding signage signal amplification circuit based on an anti-theft system for merchandise, so as to solve or alleviate the technical problems existing in the prior art, and at least provide a beneficial choice.

The technical scheme of the embodiment of the utility model is realized as follows: a self-ringing signage signal amplification circuit based on an article surveillance system, comprising:

the control circuit, the sign protection circuit, the small signal receiving and amplifying circuit, the power supply circuit and the alarm circuit are respectively connected with the control circuit, and the sign protection circuit, the small signal receiving and amplifying circuit and the alarm circuit are respectively connected with the power supply circuit.

Further preferred is: the small signal receiving and amplifying circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a capacitor C7, a capacitor C8 and an inductor L4, a triode Q1, a triode Q2, a triode Q4 and a triode Q3.

Further preferred is: the pin B of the triode Q1 is respectively connected with one end of an inductor L4, a capacitor C2, a capacitor C1 and a resistor R1 which are mutually connected in parallel through a capacitor C3, and the pin B of the triode Q1 is respectively connected with the other end of the inductor L4, the capacitor C2, the capacitor C1 and the resistor R1 which are mutually connected in parallel through a resistor R3 and grounded;

The B pin of the triode Q1 is connected with the E pin of the triode Q3 through a resistor R2, the E pin of the triode Q1 is grounded through a resistor R5, the resistor R5 is connected in parallel with a capacitor C4, the C pin of the triode Q1 is connected with the E pin of the triode Q3 through a resistor R4, the C pin of the triode Q1 is connected with the B pin of the triode Q2 through a capacitor C5, the B pin of the triode Q2 is grounded through a resistor R7, the B pin of the triode Q2 is connected with the E pin of the triode Q3 through a resistor R6, the E pin of the triode Q2 is grounded through a resistor R9, the resistor R9 is connected in parallel with a capacitor C7, the C pin of the triode Q2 is connected with the E pin of the triode Q3 through a resistor R8, the C pin of the triode Q2 is connected with the B pin of the triode Q3 through a capacitor C6, the C pin of the triode Q3 is grounded through a resistor R12, and the resistor R12 is connected with the capacitor C8 in parallel; the pin B of the triode Q3 is grounded through a resistor R11, the pin B of the triode Q3 is connected with the VCC end through a resistor R10, and the pin E of the triode Q3 is connected with the VCC end;

The C pin of the triode Q3 is connected with the B pin of the triode Q4 through a resistor R13, the E pin of the triode Q4 is grounded, and the C pin of the triode Q4 is connected with the VCC end through a resistor R14.

Further preferred is: the model of the triode Q1, the triode Q2 and the triode Q4 is 2SC2412K, and the model of the triode Q3 is 2SA1037AK.

Further preferred is: and the pins B, C and E of the triode Q1, the triode Q2, the triode Q4 and the triode Q3 are respectively a base electrode, a collector electrode and an emitter electrode.

By adopting the technical scheme, the embodiment of the utility model has the following advantages:

The utility model has the advantages that the signal amplification factor is large, the waveform is not deformed, the current consumption is low, smaller signals can be detected, the small signal amplification is realized by adopting an integrated operational amplifier IC, and the self-sounding sign of the commodity anti-theft system is matched with the commodity anti-theft system for use, so that the dual protection functions of sign alarm and host alarm are realized. Is mainly used for protecting valuable commodities such as sports goods, leather bags, high-grade clothes and the like. When the binding band bound on the commodity is pulled out or sheared off, or the label is peeled off and stuck to the commodity, the label can give out a loud audible and visual alarm, and simultaneously, the host machine can be triggered to give an alarm, so that double protection is realized, and the theft is prevented.

The foregoing summary is for the purpose of the specification only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present utility model will become apparent by reference to the drawings and the following detailed description.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are necessary for the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a radio frequency circuit based on an article surveillance system of the present utility model;

fig. 2 is a circuit diagram of the signal detection circuit of the present utility model.

Reference numerals: 10. a control circuit; 20. a signage protection circuit; 30. a small signal receiving and amplifying circuit; 40. a power supply circuit; 50. and an alarm circuit.

Detailed Description

Hereinafter, only certain exemplary embodiments are briefly described. As will be recognized by those of skill in the pertinent art, the described embodiments may be modified in various different ways without departing from the spirit or scope of the present utility model. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.

Embodiments of the present utility model will be described in detail below with reference to the accompanying drawings.

One embodiment

As shown in fig. 1-2, an embodiment of the present utility model provides a self-ringing signage signal amplification circuit based on an anti-theft system for commodities, including:

The control circuit 10, the label protection circuit 20, the small signal receiving and amplifying circuit 30, the power supply circuit 40 and the alarm circuit 50 are respectively connected with the control circuit 10, and the label protection circuit 20, the small signal receiving and amplifying circuit 30 and the alarm circuit 50 are respectively connected with the power supply circuit 40.

The input end of the power circuit 40 is a 3.3V button battery, and 3.3V voltage is output to each circuit for power supply; the control circuit 10 is a core control center, monitors the signal states of the tag protection circuit 20 and the small signal receiving circuit 30 in real time, and when the tag protection circuit 20 and the small signal receiving circuit 30 are in a dormant state, the self-sounding tag of the commodity anti-theft system is awakened to work when the tag protection circuit 20 and the small signal receiving circuit 30 have signal changes, when the input level of the tag protection circuit 20 is changed from low level to high level, the binding band bound on the commodity is pulled out or sheared off, or the tag is peeled off and stuck commodity, at the moment, the control circuit 10 outputs a signal with the alarm frequency of 3KHz to the alarm circuit 50, outputs an audible and visual alarm, when the signal period input by the small signal receiving and amplifying circuit 30 is a specified periodic signal, the control circuit 10 also outputs a signal with the alarm frequency of 3KHz to the alarm circuit 50, and outputs an audible and visual alarm, and when the signal period input by the small signal receiving and amplifying circuit 30 is a period of releasing the alarm signal, the control circuit 10 stops outputting the alarm signal to the alarm circuit 50.

Another embodiment: the small signal receiving and amplifying circuit 30 includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a capacitor C7, a capacitor C8, an inductor L4, a transistor Q1, a transistor Q2, a transistor Q4, and a transistor Q3.

Further specific is: the pin B of the triode Q1 is respectively connected with one end of an inductor L4, a capacitor C2, a capacitor C1 and a resistor R1 which are mutually connected in parallel through a capacitor C3, and the pin B of the triode Q1 is respectively connected with the other end of the inductor L4, the capacitor C2, the capacitor C1 and the resistor R1 which are mutually connected in parallel through a resistor R3 and grounded;

The B pin of the triode Q1 is connected with the E pin of the triode Q3 through a resistor R2, the E pin of the triode Q1 is grounded through a resistor R5, the resistor R5 is connected in parallel with a capacitor C4, the C pin of the triode Q1 is connected with the E pin of the triode Q3 through a resistor R4, the C pin of the triode Q1 is connected with the B pin of the triode Q2 through a capacitor C5, the B pin of the triode Q2 is grounded through a resistor R7, the B pin of the triode Q2 is connected with the E pin of the triode Q3 through a resistor R6, the E pin of the triode Q2 is grounded through a resistor R9, the resistor R9 is connected in parallel with a capacitor C7, the C pin of the triode Q2 is connected with the E pin of the triode Q3 through a resistor R8, the C pin of the triode Q2 is connected with the B pin of the triode Q3 through a capacitor C6, the C pin of the triode Q3 is grounded through a resistor R12, and the resistor R12 is connected with the capacitor C8 in parallel; the pin B of the triode Q3 is grounded through a resistor R11, the pin B of the triode Q3 is connected with the VCC end through a resistor R10, and the pin E of the triode Q3 is connected with the VCC end;

The C pin of the triode Q3 is connected with the B pin of the triode Q4 through a resistor R13, the E pin of the triode Q4 is grounded, and the C pin of the triode Q4 is connected with the VCC end through a resistor R14.

The inductor L4, the capacitor C1 and the capacitor C2 form an LC resonant circuit for receiving wireless signals near a self-ringing label of the commodity anti-theft system, the resistor R1 and the inductor L4 are connected in parallel and used for adjusting the sensitivity of the received signals of the LC, the inductor L4, the capacitor C2, the capacitor C1 and the resistor R1 are connected in parallel, one end is grounded, the other end of the capacitor C3 is grounded, the other end is connected with the resistor R3 and the resistor R2, the base electrode of the triode Q1 is grounded, the other end of the resistor R3 is connected with the power VCC, the emitter electrode of the triode Q1 is connected with the resistor R5 and the capacitor C4, the other end of the resistor R4 is connected with the power VCC, the other end of the capacitor C5 is connected with the resistor R7 and the resistor R6, and the base electrode of the triode Q2, the other end of the resistor R7 is grounded, the other end of the resistor R6 is grounded, the emitter of the triode Q2 is grounded, the resistor R9 and the capacitor C7 are grounded, the other ends of the resistor R9 and the capacitor C7 are grounded, the collector of the triode Q2 is grounded, the resistor R8 is grounded, the other ends of the capacitor C6 are grounded, the resistor R11 and the resistor R10 are grounded, the other ends of the resistor R11 are grounded, the other ends of the resistor R10 are grounded, the emitter of the triode Q3 is grounded, the collector of the triode Q3 is grounded, the resistor R12 and the resistor R13 are grounded, the other ends of the resistor R12 and the capacitor C8 are grounded, the other ends of the resistor R13 are grounded, the emitter of the triode Q4 is grounded, and the collector of the triode Q4 is grounded, the resistor R14 and the output Signal Signal are grounded to the control circuit 10.

Further specific is: the model of the triode Q1, the triode Q2 and the triode Q4 is 2SC2412K, and the model of the triode Q3 is 2SA1037AK.

Further specific is: and the pins B, C and E of the triode Q1, the triode Q2, the triode Q4 and the triode Q3 are respectively a base electrode, a collector electrode and an emitter electrode.

A self-ringing sign signal amplifying circuit based on commodity anti-theft system is characterized by that the wireless signal near the self-ringing sign is received by LC, the received signal is amplified by two-stage common emitter discharge circuit and one-stage common collector discharge circuit, then the amplified sine wave signal is detected as square wave signal, and outputted to control circuit 10, the control circuit 10 calculates the periodic signal of square wave by means of timer, so that it can judge that the received signal is the useful signal of commodity anti-theft system or the remote controller signal for releasing alarm.

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The foregoing is merely illustrative of the present utility model, and the present utility model is not limited thereto, and any person skilled in the art will readily recognize that various changes and substitutions are possible within the scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the protection scope of the claims.