CN219758906U - Anti-theft device based on infrared - Google Patents

Abstract

The utility model relates to an infrared-based anti-theft device, which is characterized in that: the infrared sensor is sequentially connected with the amplifying circuit, the A/D converting circuit and the microprocessor and is used for amplifying the electric signals, converting the A/D signals into the microprocessor and transmitting the electric signals to the microprocessor, and the buzzer is connected with the microprocessor. The utility model uses infrared technology to monitor the temperature change of the object surface, which can monitor whether the object is in safe environment or not, and can also prevent theft and alarm.

Description

Anti-theft device based on infrared

Technical Field

The utility model relates to the field of burglary prevention, in particular to an infrared-based burglary prevention device.

Background

Precious collections such as calligraphy and painting, bronze porcelain, etc. collected in museums, institutions or private organizations are considered to be properly preserved and theft-proof. The glass cabinet has the advantages that the glass cabinet is special in storage of some articles, common physical injury can be resisted, the exhibited articles and the external environment of the exhibited are isolated, the concerned limbs are forbidden to contact, and the anti-theft effect can be achieved.

Some articles are stored with certain requirements on the environment, such as temperature requirements, light-afraid and the like, and the common glass showcase can resist the damage of external force to the exhibited articles, but cannot timely reflect the temperature change of the environment where the exhibited articles are located. The monitoring and anti-theft technology by means of a camera is to set up a monitor to detect whether the display place of the collection is abnormal or not, and the method needs to arrange special personnel to watch videos to judge the abnormality. Therefore, the anti-theft device can monitor and control whether the articles are safe or not in real time, and can not destroy the detected articles to be qualified for the anti-theft protection work of important articles.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model provides the anti-theft device based on infrared, which utilizes the infrared technology to monitor the body surface temperature change of the article at regular time, thereby monitoring whether the article is in a safe preservation environment or not and giving an anti-theft alarm.

In order to solve the technical problems, the utility model adopts the following technical scheme: the utility model provides an anti-theft device based on infrared, including optical system, infrared sensor, electronic circuit and bee calling organ, optical system includes fresnel optical lens, fresnel optical lens is used for absorbing infrared radiation and links to each other with infrared sensor, infrared sensor converts the light signal into the electrical signal, electronic circuit includes amplifier circuit, AD conversion circuit and microprocessor, infrared sensor links to each other with amplifier circuit, AD conversion circuit, microprocessor in proper order for amplify, AD conversion and send to microprocessor to the electrical signal, bee calling organ links to each other with microprocessor.

Further, the optical system further comprises an optical filter, and the optical filter is positioned in front of the Fresnel optical lens.

Further, the infrared temperature sensor is a pyroelectric infrared sensor.

Furthermore, the microprocessor is connected with the upper computer through a serial port.

Further, the microprocessor is connected with a key combination display screen.

The utility model has the beneficial effects that: the anti-theft device based on infrared well solves the anti-theft problem, can protect articles, does not interfere or damage the articles, and can monitor the body surface of the articles. When the infrared device is used, the alarm threshold can be adjusted, the body surface temperature of the monitored object exceeds the threshold, an alarm mechanism is triggered, a buzzer is arranged at the front end for alarm, and a software pop-up window of an upper computer is used for alarm. The device has the advantages of relatively low cost, low energy consumption, simple operation, perfect functions, strong adaptability and strong safety.

Drawings

FIG. 1 is a schematic illustration of the present utility model;

FIG. 2 is a schematic view of a Fresnel lens;

FIG. 3 is a schematic diagram of an embodiment of the present utility model;

FIG. 4 is a schematic diagram of a singlechip and buzzer key circuit;

FIG. 5 is a schematic diagram of an infrared thermometry and screen display;

1. fresnel lens, 2, fresnel surface.

Detailed Description

Example 1

The technical solutions in the embodiments of the present utility model will be clearly and completely described below. The described embodiments of the utility model are only some, but not all, embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The embodiment discloses an anti-theft device based on infrared, as shown in fig. 1 and 3, the anti-theft device comprises an optical system, an infrared sensor, an electronic circuit and a buzzer, wherein the optical system comprises a Fresnel optical lens, the Fresnel optical lens is used for absorbing infrared radiation and is connected with the infrared sensor, the infrared sensor converts an optical signal into an electric signal, the electronic circuit comprises an amplifying circuit, an A/D (analog to digital) conversion circuit and a microprocessor, the infrared sensor is sequentially connected with the amplifying circuit, the A/D conversion circuit and the microprocessor and is used for amplifying the electric signal, converting the A/D signal into the microprocessor and transmitting the signal to the microprocessor, and the buzzer is connected with the microprocessor.

The device realizes the principle of theft prevention as follows: in nature, all objects with temperatures above absolute zero are constantly emitting infrared radiant energy into the surrounding space. And the temperature of the object depends on the kinetic energy of the particles, such as atoms, molecules, etc. therein. In physics, the planck's law of blackbody radiation (also simply called planck's law or law of blackbody radiation) is used to describe: the emissivity of electromagnetic radiation emitted from a black body is related to frequency to each other at any temperature T.

The relationship between the wavelength and the frequency of electromagnetic waves is λ=c/v. The infrared radiation quantity of the target in the wave band range is measured, and then the temperature of the measured target is calculated by a thermometer. The device passively absorbs the infrared radiation energy of the monitored object by monitoring the body surface infrared radiation light of the object, the infrared temperature sensor converts the optical signal into an electric signal, the electric signal is connected into a signal amplifier, and the temperature is calculated after the signal amplification, so that the accurate temperature value of the surface of the object is obtained. Judging whether the temperature value of the object exceeds a set threshold value, if so, putting the object in an unsafe state, and if the monitored temperature is too low or too high, alarming by a buzzer; when the monitoring object moves greatly, the device monitors the temperature fluctuation of the object and sounds the anti-theft alarm.

As shown in fig. 2, one surface of the fresnel lens 1 is a smooth surface, and concentric circles from small to large are inscribed on the other surface to form a fresnel surface 2. Fresnel optical lenses function in two ways: the focusing function is that the pyroelectric infrared signal is refracted (reflected) on the infrared sensor, and the second function is that a plurality of bright areas and dark areas are divided into the detection area, so that a moving object entering the detection area can generate a variable pyroelectric infrared signal on the infrared sensor in a temperature change mode, and the effect is good. The infrared detector has the advantages of less mirror body heat energy absorption, less scattering loss, high efficiency, higher imaging precision, long detection distance and the like, and is suitable for being used for a long-distance and large-range passive infrared detector. In the process of absorbing infrared radiation by the optical system, an optical filter is arranged in front of the Fresnel optical lens, and firstly, radiation light emitted by a stray light monitor is filtered by the optical filter and firstly passes through the optical system.

In this embodiment, the infrared temperature sensor is a pyroelectric infrared sensor. When the pyroelectric infrared sensor receives infrared light irradiation of non-constant intensity, a temperature rise is caused, which causes a voltage clicked on the sensor surface to change accordingly, and an optical signal is converted into an electrical signal. The infrared energy is focused on the photodetector and converted into a corresponding electrical signal. After the signal is amplified by the amplifier circuit, the AD module converts the analog signal into a digital signal and then processes the digital signal by the microprocessor.

In this embodiment, the microprocessor is connected to the upper computer through a serial port. And the microprocessor is connected with a key combination display screen.

The following functions can be realized through the microprocessor and the peripheral mechanism thereof:

1. the display screen displays the monitoring temperature;

2. transmitting temperature data to the upper computer through serial port communication, comparing the data transmitted by the upper computer software with a threshold value, and alarming by the upper computer software when the data exceeds the threshold value;

3. if the temperature value exceeds the threshold value, the buzzer sounds an alarm.

The upper computer receives the temperature information sent by the device at regular time. If all are normal, the data are stored, the temperature transformation is displayed in a broken line statistical diagram mode, and if abnormal values are encountered, an alarm is given. Meanwhile, the software sets a threshold value for monitoring the body surface temperature according to the self condition of the monitored object and sets data acquired every few seconds. And judging whether the acquired temperature data exceeds a threshold value, whether an object is separated from an infrared monitoring range or not, and whether the temperature is too high or not. If the data is normal, the command is not sent out so as to trigger the buzzer to play the audio alarm, the data is sent to software on a computer, and the data is stored in a database; conversely, the buzzer immediately gives an alarm, and the computer pops up a prompt.

Key group: and (5) opening and closing the anti-theft monitoring, and setting a temperature threshold value and timing time.

And (3) a display screen: the temperature of the monitored object, the threshold value, etc. are displayed.

The alarm is divided into:

first, the monitoring object breaks away from the monitoring of the device and gives out an anti-theft alarm, and the body surface temperature of the object is continuously detected. When the object is suddenly changed from the original position, the monitored data is abnormal, and whether the object is taken away or not is judged, or the object is swayed to generate offset and break away monitoring. The monitored object appears as: normal state, abnormal state. Normal state: the temperature data of the monitored object is within the set threshold range and does not exceed the threshold, the difference between the obtained data and the front and back time nodes is small, and the data are normal; abnormal state: the temperature data of the monitored object exceeds the threshold value, abnormal data is obtained to exceed the threshold value for a certain time, and the data is abnormal for exceeding the set time, so that the possibility of false alarm is eliminated, and the abnormal state is judged, namely the monitored object is displaced or taken away. If displacement only occurs, the exhibited article is still in the position, a plurality of monitoring points can be arranged at the monitoring end, one monitoring point finds monitoring abnormality, and other points can monitor the normal temperature of the exhibited article and do not trigger an alarm; if the temperature is taken away, all the monitoring points detect that the temperature exceeds the threshold value, and the upper computer detects that the temperature fluctuation is large, and then the upper computer alarms and prompts.

Secondly, monitoring whether the temperature of the object table is too high or too low, alarming by using a buzzer, comparing the data obtained by the upper computer software with the threshold, and popping up an alarm frame by using the upper computer when the data is beyond the threshold, and recording alarm information (time, abnormal temperature, set threshold and the like) by using a database. The device then determines a prompt that the environment is unsuitable for storage of the monitored item.

The foregoing description is only of the basic principles and preferred embodiments of the present utility model, and modifications and alternatives thereto will occur to those skilled in the art to which the present utility model pertains, as defined by the appended claims.

Claims (5)

1. An infrared-based anti-theft device, characterized in that: the infrared sensor is sequentially connected with the amplifying circuit, the A/D converting circuit and the microprocessor and is used for amplifying the electric signals, converting the A/D signals into the microprocessor and transmitting the electric signals to the microprocessor, and the buzzer is connected with the microprocessor.

2. The infrared-based anti-theft device of claim 1, wherein: the optical system further includes a filter positioned in front of the fresnel optical lens.

3. The infrared-based anti-theft device of claim 1, wherein: the infrared temperature sensor is a pyroelectric infrared sensor.

4. The infrared-based anti-theft device of claim 1, wherein: the microprocessor is connected with the upper computer through a serial port.

5. The infrared-based anti-theft device of claim 1, wherein: the microprocessor is connected with a key combination display screen.