Building inspection device

Abstract

The present application provides a building detection device. The building detection device includes: a first capacitor plate, a second capacitor plate, a third capacitor plate, a multi-frequency oscillation circuit, a logic gate circuit and a control circuit. The first capacitor plate, the second capacitor plate and the third capacitor plate are arranged at intervals in the horizontal direction. The first capacitor plate, the third capacitor plate, the control circuit and the first end of the multi-frequency oscillation circuit are connected in common. The second capacitor plate is electrically connected to the second end of the multi-frequency oscillation circuit. The logic gate circuit is electrically connected to the multi-frequency oscillation circuit and the control circuit respectively. The multi-frequency oscillation circuit is used to output a first square wave signal and a second square wave signal. When no foreign matter is detected, the control circuit is used to calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit. After calibration, the logic gate circuit outputs a first voltage according to the first square wave signal and the second square wave signal. The control circuit is used to determine whether there is a foreign matter in the building according to the first voltage and a preset voltage threshold.

Description

Technical Field

[0001] The present application relates to the technical field of building structure detection, and in particular to a building detection device. Background Art

[0002] At present, during the process of upgrading, renovating or maintaining a building, it is often necessary to cut or drill holes in walls, floors and other places. In the current house structure, the walls, floors and other load-bearing structures of the building need to be built with steel bars and wooden beams to strengthen the structural strength. When facing maintenance and renovation work, it is usually impossible to know the exact location of objects such as steel bars, wooden beams and wires hidden in the building.

[0003] Existing traditional metal detection solutions can only identify and detect steel bars or steel plates inside buildings, but cannot detect non-ferrous foreign objects such as plastic water pipes and wooden beams. Summary of the invention

[0004] Based on this, it is necessary to provide a building detection device to address the problem that existing metal detection solutions can only identify and detect steel bars or steel plates in buildings, but cannot detect non-ferrous foreign objects such as plastic water pipes and wooden beams.

[0005] A building detection device comprises: a first capacitor plate, a second capacitor plate, a third capacitor plate, a multi-frequency oscillation circuit, a logic gate circuit and a control circuit;

[0006] The first capacitor plate, the second capacitor plate and the third capacitor plate are arranged at intervals in the horizontal direction, the output end of the first capacitor plate, the output end of the third capacitor plate, the first end of the control circuit and the first end of the multi-frequency oscillation circuit are connected in common, the output end of the second capacitor plate is electrically connected to the second end of the multi-frequency oscillation circuit, the first end of the logic gate circuit is electrically connected to the third end of the multi-frequency oscillation circuit, the second end of the logic gate circuit is electrically connected to the fourth end of the multi-frequency oscillation circuit, and the third end of the logic gate circuit is electrically connected to the second end of the control circuit;

[0007] The multi-frequency oscillation circuit is used to output a first square wave signal according to the detection signals of the first capacitor plate and the third capacitor plate, and to output a second square wave signal according to the detection signal of the second capacitor plate. When no foreign object is detected, the control circuit is used to calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit. After calibration, the logic gate circuit outputs a first voltage according to the first square wave signal and the second square wave signal. The control circuit is used to determine whether there is a foreign object in the building based on the first voltage and a preset voltage threshold.

[0008] In one of the embodiments, the control circuit is used to compare the first voltage with the preset voltage threshold;

[0009] If the first voltage is greater than the preset voltage threshold, it is determined that there is a foreign object in the building body corresponding to the second capacitor plate.

[0010] In one embodiment, the control circuit is used to calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit, which means:

[0011] The control circuit is used to output a bias voltage, and adjust the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit based on the bias voltage, so that the first square wave signal and the second square wave signal are complementary.

[0012] In one of the embodiments, the control circuit is further configured to obtain a plurality of the first voltages within a preset period and calculate a real-time variance of the plurality of the first voltages, and determine the preset voltage threshold based on the real-time variance and a fixed offset.

[0013] In one embodiment, the building detection device further includes:

[0014] A detection antenna, used for detecting a charged conductor and outputting a detection signal;

[0015] an amplifying circuit, electrically connected to the detection antenna and the third end of the control circuit respectively, and configured to amplify the detection signal and output it to the control circuit;

[0016] The control circuit determines whether there is a live conductor in the building based on the amplified detection signal.

[0017] In one embodiment, the control circuit calculates the amplitude based on the amplified detection signal and compares the amplitude with a preset amplitude threshold. If the amplitude is greater than the preset amplitude threshold, it is determined that there is a charged conductor in the building corresponding to the current building detection device.

[0018] In one embodiment, the amplification circuit includes:

[0019] A capacitor, a first end of which is electrically connected to the detection antenna;

[0020] an amplifier, wherein a first end of the amplifier is electrically connected to a second end of the capacitor, and a second end of the amplifier is electrically connected to a third end of the control circuit;

[0021] a first resistor, wherein a first end of the first resistor is commonly connected to a first end of the amplifier and a second end of the capacitor, and a second end of the first resistor is electrically connected to a second end of the amplifier; and

[0022] A bias circuit, wherein a first end of the bias circuit is electrically connected to a power supply, a second end of the bias circuit is electrically connected to a third end of the amplifier, and a third end of the bias circuit is grounded.

[0023] In one embodiment, the control circuit comprises:

[0024] a bias generator, wherein a first end of the bias generator is commonly connected to an output end of the first capacitor plate and an output end of the third capacitor plate, and is used to output a bias voltage, and calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit based on the bias voltage when no foreign object is detected; and

[0025] A controller, wherein a first end of the controller is electrically connected to a second end of the bias generator, a second end of the controller is electrically connected to a third end of the logic gate circuit, and the controller is used to determine whether there is a foreign object in the building according to the first voltage and a preset voltage threshold.

[0026] In one embodiment, the building detection device further includes:

[0027] A second resistor, wherein a first end of the second resistor is commonly connected to an output end of the first capacitor plate and an output end of the third capacitor plate, and a second end of the second resistor is electrically connected to a first end of the multi-frequency oscillation circuit.

[0028] In one embodiment, the building detection device further includes:

[0029] A third resistor, wherein a first end of the third resistor is connected to the output end of the second capacitor plate, and a second end of the third resistor is electrically connected to the second end of the multi-frequency oscillation circuit.

[0030] In one embodiment, the building detection device further includes:

[0031] An alarm is electrically connected to the fourth end of the control circuit.

[0032] In one embodiment, the building detection device further includes:

[0033] A filter circuit, wherein a first end of the filter circuit is electrically connected to a third end of the logic gate circuit, and a second end of the filter circuit is electrically connected to a second end of the control circuit.

[0034] Compared with the prior art, the above-mentioned building detection device outputs a first square wave signal according to the detection signals of the first capacitor plate and the third capacitor plate through the multi-frequency oscillation circuit, and outputs a second square wave signal according to the detection signal of the second capacitor plate. When no foreign matter is detected, the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit are calibrated through the control circuit. After calibration, the logic gate circuit outputs a first voltage according to the first square wave signal and the second square wave signal. The control circuit determines whether there is a foreign matter in the building according to the first voltage and the preset voltage threshold, thereby realizing accurate detection of non-ferrous foreign matters such as plastic water pipes and wooden beams in the building. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 A circuit schematic diagram of a building detection device provided in one embodiment of the present application;

[0037] Figure 2 An equivalent diagram of capacitance detection provided by an embodiment of the present application;

[0038] Figure 3 A dielectric constant distribution diagram of a building containing hidden foreign matter provided in one embodiment of the present application;

[0039] Figure 4 A diagram of a calibrated square wave signal provided in an embodiment of the present application;

[0040] Figure 5 A partial circuit diagram of a building detection device provided in one embodiment of the present application;

[0041] Figure 6 A partial circuit diagram of a building detection device provided in another embodiment of the present application.

[0042] Description of reference numerals:

[0043] 10. Building detection device; 101. Building; 110. First capacitor plate; 111. Second resistor; 120. Second capacitor plate; 121. Third resistor; 130. Third capacitor plate; 200. Multi-frequency oscillation circuit; 300. Logic gate circuit; 400. Control circuit; 410. Bias generator; 420. Controller; 500. Detection antenna; 600. Amplifier circuit; 601. Power supply; 610. Capacitor; 620. Amplifier; 630. First resistor; 640. Bias circuit; 641. Fourth resistor; 642. Fifth resistor; 710. Alarm; 720. Filter circuit. DETAILED DESCRIPTION

[0044] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific implementation disclosed below.

[0045] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0046] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0048] See also Figure 1, an embodiment of the present application provides a building detection device 10, which can detect foreign objects such as metal objects, water pipes, wood, etc. hidden in a building 101. The building detection device 10 includes: a first capacitor plate 110, a second capacitor plate 120, a third capacitor plate 130, a multi-frequency oscillation circuit 200, a logic gate circuit 300 and a control circuit 400. The first capacitor plate 110, the second capacitor plate 120 and the third capacitor plate 130 are arranged at intervals in the horizontal direction. The output end of the first capacitor plate 110, the output end of the third capacitor plate 130, the first end of the control circuit 400 and the first end of the multi-frequency oscillation circuit 200 are connected in common. The output end of the second capacitor plate 120 is electrically connected to the second end of the multi-frequency oscillation circuit 200. The first end of the logic gate circuit 300 is electrically connected to the third end of the multi-frequency oscillation circuit 200. The second end of the logic gate circuit 300 is electrically connected to the fourth end of the multi-frequency oscillation circuit 200. The third terminal of the logic gate circuit 300 is electrically connected to the second terminal of the control circuit 400 .

[0049] The multi-frequency oscillation circuit 200 is used to output a first square wave signal according to the detection signal of the first capacitor plate 110 and the third capacitor plate 130, and output a second square wave signal according to the detection signal of the second capacitor plate 120. When no foreign matter is detected, the control circuit 400 is used to calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200. After calibration, the logic gate circuit 300 outputs a first voltage according to the first square wave signal and the second square wave signal. The control circuit 400 is used to determine whether there is a foreign matter in the building 101 according to the first voltage and a preset voltage threshold.

[0050] In one embodiment, the area of ​​the first capacitor plate 110 can be selected according to actual needs, and no specific numerical value is limited here. In one embodiment, the shape of the first capacitor plate 110 can be square, circular, etc. Similarly, the second capacitor plate 120 and the third capacitor plate 130 can adopt the same structure as the first capacitor plate 110. In one embodiment, the first capacitor plate 110, the second capacitor plate 120 and the third capacitor plate 130 can be arranged on a PCB (Printed Circuit Board) board at intervals in the horizontal direction. When in use, the PCB board can be directly attached to the building body 101.

[0051] It can be understood that the specific circuit structure of the multi-frequency oscillation circuit 200 is not limited, as long as it has the function of outputting the first square wave signal according to the detection signal of the first capacitor plate 110 and the third capacitor plate 130, and outputting the second square wave signal according to the detection signal of the second capacitor plate 120. In one embodiment, the multi-frequency oscillation circuit 200 can be composed of two multi-frequency oscillators. One of the multi-frequency oscillators can be used to output the first square wave signal according to the detection signal of the first capacitor plate 110 and the third capacitor plate 130. The other multi-frequency oscillator can be used to output the second square wave signal according to the detection signal of the second capacitor plate 120.

[0052] In one embodiment, the driving signal of the multi-frequency oscillation circuit 200 can be output through the control circuit 400. In one embodiment, the multi-frequency oscillation circuit 200 and the logic gate circuit 300 can be provided with power through a power module. The power module can be a dry cell, a storage battery, etc.

[0053] It can be understood that the specific circuit structure of the control circuit 400 is not limited, as long as it has the function of determining whether there is a foreign object in the building body 101 according to the first voltage and the preset voltage threshold. In one embodiment, the control circuit 400 can be an MCU (micro control unit). In one embodiment, the control circuit 400 can also be other integrated IC chips.

[0054] When the building detection device 10 is in use, the dielectric constant of the building 101 can be detected in real time through the capacitor plate group composed of the first capacitor plate 110 and the third capacitor plate 130, and a first detection signal can be output to the multi-frequency oscillation circuit 200. The multi-frequency oscillation circuit 200 can output the first square wave signal according to the first detection signal. The first detection signal is a voltage signal. Similarly, the building 101 can be detected in real time through the second capacitor plate 120, and a second detection signal can be output to the multi-frequency oscillation circuit 200. The multi-frequency oscillation circuit 200 can output the second square wave signal according to the second detection signal. The second detection signal is a voltage signal.

[0055] Since the duty cycle in the square wave signal is controlled by the charging time constant of the capacitor plates (i.e., the first capacitor plate 110, the second capacitor plate 120, and the third capacitor plate 130), the duty cycle varies with the capacitance C. The specific capacitance calculation formula is: C = εS / 4πkd. Where π and k are constants. The capacitance C is affected by the capacitance plate area S, the capacitance plate distance d, and the dielectric constant ε. Figure 2As shown, the capacitor plate is printed on a PCB, and the PCB is attached to the building 101. That is, the capacitor plate is attached to the building 101. At the same time, the plate corresponding to the capacitor plate is equivalent to being infinitely far away, and the distance d is equivalent to a constant. The area of ​​the capacitor plate is the size of the copper area printed on the PCB. The dielectric material is equivalent to the tested building 101, so the capacitor C is only affected by the dielectric constant ε (the change in the dielectric constant of air is ignored here).

[0056] From the above analysis, it can be seen that the dielectric constant of the building 101 can be reflected by indirectly measuring the capacitance value of the building. When other foreign objects such as water pipes, wood, metal, etc. are hidden in the building 101, the total dielectric constant reflected will be specific to the dielectric constant of the building (such as Figure 3 As shown). That is, by measuring the capacitance value of the building 101, it can be determined whether there is a hidden foreign object in the building 101. The capacitance value of the building 101 changes linearly with the duty cycle of the square wave signal (i.e., the first square wave signal and the second square wave signal). In other words, it can be determined whether there is a hidden foreign object in the building 101 by the square wave signal.

[0057] In one embodiment, after the multi-frequency oscillation circuit 200 outputs the first square wave signal and the second square wave signal, the first square wave signal and the second square wave signal may be calibrated first. Specifically, after the multi-frequency oscillation circuit 200 outputs the first square wave signal and the second square wave signal, and at this time, when the building 101 corresponding to the building detection device 10 does not hide any foreign matter, the control circuit 400 may output a bias voltage, and adjust the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200 based on the bias voltage, so that the first square wave signal and the second square wave signal are complementary. That is, the control circuit 400 calibrates the first square wave signal and the second square wave signal based on the bias voltage, so that the first square wave signal and the second square wave signal are completely complementary (such as Figure 4 shown).

[0058] In one embodiment, if the first square wave signal and the second square wave signal are calibrated, and the building 101 corresponding to the building detection device 10 hides foreign objects, the building detection device 10 can be moved to the building 101 where no foreign objects are hidden for calibration. After calibration, the first square wave signal and the second square wave signal can be converted into one square wave signal through the logic gate circuit 300 and the first voltage can be output. That is, at this time, the logic gate circuit 300 outputs the first voltage to the control circuit 400. In one embodiment, the logic gate circuit 300 can be a NOR gate.

[0059] In one embodiment, after receiving the first voltage, the control circuit 400 may compare the first voltage with the preset voltage threshold. If the first voltage is greater than the preset voltage threshold, it is determined that there is a foreign object in the building body 101 corresponding to the second capacitor plate 120. That is, the first capacitor plate 110, the second capacitor plate 120 and the third capacitor plate 130 move to an area with foreign objects, and at this time, the logic gate circuit 300 outputs a mutation in the first voltage, and the first voltage at the mutation point is greater than the preset voltage threshold. In this way, it can be determined that there is a foreign object in the area of ​​the building body 101 corresponding to the building body detection device 10 at this time.

[0060] On the contrary, if the first voltage is less than or equal to the preset voltage threshold, it is determined that there is no foreign matter in the building 101 corresponding to the second capacitor plate 120. That is, at this time, there is no foreign matter in the area of ​​the building 101 corresponding to the building detection device 10. At this time, the building detection device 10 can be moved to detect other areas of the building 101. In this way, the above logic can be used to detect whether there are foreign matters such as metal objects, water pipes, and wood in the building 101, thereby improving the accuracy of the detection. In one embodiment, the preset voltage threshold can be selected according to actual needs, and no specific numerical value is limited here.

[0061] In this embodiment, the multi-frequency oscillation circuit 200 outputs a first square wave signal according to the detection signal of the first capacitor plate 110 and the third capacitor plate 130, and outputs a second square wave signal according to the detection signal of the second capacitor plate 120. When no foreign matter is detected, the control circuit 400 calibrates the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200. After calibration, the logic gate circuit 300 outputs a first voltage according to the first square wave signal and the second square wave signal. The control circuit 400 determines whether there is a foreign matter in the building 101 based on the first voltage and the preset voltage threshold, thereby accurately detecting non-ferrous foreign matter such as plastic water pipes and wooden beams in the building 101.

[0062] In one embodiment, the control circuit 400 is further configured to obtain a plurality of the first voltages within a preset period and calculate a real-time variance of the plurality of the first voltages, and determine the preset voltage threshold based on the real-time variance and a fixed offset. In one embodiment, the specific time of the preset period can be set according to actual needs, for example, the preset period can be set to 20s, 30s, etc.

[0063] In one embodiment, since the capacitor plate is printed on a PCB board, the thermal expansion and contraction of the PCB board will cause the area of ​​the capacitor plate to change in size, which will cause temperature drift during the test process. Temperature drift will cause errors in measuring foreign objects. In this way, the control circuit 400 can obtain multiple first voltages within the preset period and store them in a buffer storage space. The real-time variance is calculated based on the multiple first voltages obtained. If the real-time variance is less than the set variance threshold, it is determined that the building body detection device 10 has not detected a foreign object at this time. At this time, the real-time variance and the fixed offset can be added to determine the preset voltage threshold of the next preset period. That is, the preset voltage threshold can be dynamically adjusted through the above logic, thereby ensuring that the preset voltage threshold is always at a constant sensitivity and improving the detection accuracy.

[0064] See also Figure 5 In one embodiment, the building detection device 10 further includes: a detection antenna 500 and an amplifier circuit 600. The detection antenna 500 is used to detect a charged conductor and output a detection signal. The amplifier circuit 600 is electrically connected to the detection antenna 500 and the third end of the control circuit 400, respectively. The amplifier circuit 600 is used to amplify the detection signal and output it to the control circuit 400. The control circuit 400 determines whether there is a charged conductor in the building 101 based on the amplified detection signal.

[0065] In one embodiment, the detection antenna 500 is an AC induction antenna. The AC induction antenna can be electrically connected to the amplifier circuit 600 by AC coupling. The detection antenna 500 can detect the signal radiated by the charged conductor in the building 101, and output the detection signal to the amplifier circuit 600. The closer the distance between the detection antenna 500 and the charged conductor is, the stronger the detection signal output by the detection antenna 500 is. The detection signal output by the detection antenna 500 is amplified by the amplifier circuit 600 and then output to the control circuit 400.

[0066] The control circuit 400 can determine whether there is a charged conductor in the building 101 based on the amplified detection signal. Specifically, the control circuit 400 can calculate the amplitude of the detection signal based on the amplified detection signal, and compare the amplitude with a preset amplitude threshold. If the amplitude is greater than the preset amplitude threshold, it is determined that there is a charged conductor in the area of ​​the building 101 corresponding to the building detection device 10. On the contrary, if the amplitude is less than or equal to the preset amplitude threshold, it is determined that there is no charged conductor in the area of ​​the building 101 corresponding to the building detection device 10. In this way, whether there is a hidden charged conductor in the building 101 can be detected in real time by the above method, so that the building detection device 10 can detect the charged conductor. In one embodiment, the charged conductor can be a charged wire.

[0067] In one embodiment, the specific circuit topology of the amplifier circuit 600 is not limited, as long as it has the function of amplifying the detection signal and outputting it to the control circuit 400. In one embodiment, the amplifier circuit 600 may include: a capacitor 610, an amplifier 620, a first resistor 630, and a bias circuit 640. Specifically, the first end of the capacitor 610 is electrically connected to the detection antenna 500. The first end of the amplifier 620 is electrically connected to the second end of the capacitor 610. The second end of the amplifier 620 is electrically connected to the third end of the control circuit 400. The first end of the first resistor 630 is connected in common with the first end of the amplifier 620 and the second end of the capacitor 610. The second end of the first resistor 630 is electrically connected to the second end of the amplifier 620. The first end of the bias circuit 640 is used to be electrically connected to the power supply 601. The second end of the bias circuit 640 is electrically connected to the third end of the amplifier 620. The third end of the bias circuit 640 is grounded.

[0068] In one embodiment, the bias circuit 640 may include a fourth resistor 641 and a fifth resistor 642. The first end of the fourth resistor 641 is used to be electrically connected to the power supply 601. The second end of the fourth resistor 641 is connected to the first end of the fifth resistor 642 and the third end of the amplifier 620. The second end of the fifth resistor 642 is grounded. In one embodiment, the power supply 601 may be a dry cell, a storage battery, etc. The bias circuit 640 composed of the fourth resistor 641 and the fifth resistor 642 can generate a bias voltage and input it to the amplifier 620, so as to facilitate subsequent processing by the amplifier 620.

[0069] In one embodiment, a digital filtering network may be provided between the amplifier circuit 600 and the control circuit 400. The digital filtering network may be a digital filter. The amplified detection signal output by the amplifier circuit 600 may be digitally filtered by the digital filtering network to obtain a 50 / 60 Hz sinusoidal signal. Compared with analog filtering, the digital filtering method is easier to implement and has improved anti-interference capability.

[0070] See also Figure 6 In one embodiment, the control circuit 400 includes: a bias generator 410 and a controller 420. The first end of the bias generator 410 is connected to the output end of the first capacitor plate 110 and the output end of the third capacitor plate 130. The bias generator 410 is used to output a bias voltage, and calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200 based on the bias voltage when no foreign matter is detected. The first end of the controller 420 is electrically connected to the second end of the bias generator 410. The second end of the controller 420 is electrically connected to the third end of the logic gate circuit 300. The controller 420 is used to determine whether there is a foreign matter in the building 101 according to the first voltage and a preset voltage threshold.

[0071] In one embodiment, after the multi-frequency oscillation circuit 200 outputs the first square wave signal and the second square wave signal, and at this time, the building 101 corresponding to the building detection device 10 does not hide foreign objects, the controller 420 can control the bias generator 410 to output a bias voltage. The bias generator 410 can adjust the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200 based on the bias voltage, so that the first square wave signal and the second square wave signal are complementary. That is, the first square wave signal and the second square wave signal are calibrated based on the bias voltage by the bias generator 410, so that the first square wave signal and the second square wave signal are completely complementary.

[0072] After calibration, the first square wave signal and the second square wave signal can be converted into a square wave signal through the logic gate circuit 300 and the first voltage can be output. That is, at this time, the logic gate circuit 300 outputs the first voltage to the controller 420. After receiving the first voltage, the controller 420 can compare the first voltage with the preset voltage threshold. If the first voltage is greater than the preset voltage threshold, it is determined that there is a foreign object in the building body 101 corresponding to the second capacitor plate 120. That is, the first capacitor plate 110, the second capacitor plate 120 and the third capacitor plate 130 move to the area with foreign matter. At this time, the logic gate circuit 300 outputs the first voltage to produce a mutation, and the first voltage at the mutation is greater than the preset voltage threshold. In this way, it can be determined that there is a foreign object in the area of ​​the building body 101 corresponding to the building body detection device 10 at this time, thereby improving the accuracy of detection.

[0073] In one embodiment, the building detection device 10 further includes: a second resistor 111. A first end of the second resistor 111 is connected to the output end of the first capacitor plate 110 and the output end of the third capacitor plate 130. A second end of the second resistor 111 is electrically connected to a first end of the multi-frequency oscillation circuit 200. In one embodiment, the second resistor 111 may be a fixed resistance resistor.

[0074] In one embodiment, the building detection device 10 further includes: a third resistor 121. The first end of the third resistor 121 is connected in common with the output end of the second capacitor plate 120. The second end of the third resistor 121 is electrically connected to the second end of the multi-frequency oscillation circuit 200. In one embodiment, the third resistor 121 can be a resistor with a fixed resistance. In one embodiment, the resistance values ​​of the second resistor 111 and the third resistor 121 can be adjusted so that the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200 are not completely complementary before calibration. In this way, the first square wave signal and the second square wave signal can be calibrated based on the bias voltage by the control circuit 400 during operation, thereby improving the accuracy of detection.

[0075] In one embodiment, the building detection device 10 further includes: an alarm 710. The alarm 710 is electrically connected to the fourth end of the control circuit 400. In one embodiment, the type of the alarm 710 is not limited, as long as it has an alarm function. In one embodiment, the alarm 710 can be a buzzer alarm. In one embodiment, the alarm 710 can also be an LED alarm. When the building detection device 10 is in use, when the control circuit 400 determines that there is a foreign object in the area of ​​the building 101 currently corresponding to the building detection device 10 based on the first voltage and the preset voltage threshold, the alarm 710 can be used to sound an alarm to remind the staff that there is a foreign object in the current area of ​​the building 101. In this way, the detection efficiency can be improved by cooperating with the alarm 710.

[0076] In one embodiment, the building detection device 10 further includes: a filter circuit 720. A first end of the filter circuit 720 is electrically connected to a third end of the logic gate circuit 300. A second end of the filter circuit 720 is electrically connected to a second end of the control circuit 400. In one embodiment, the specific structure of the filter circuit 720 is not limited, and an RC filter circuit can be used. By filtering the first voltage output by the logic gate circuit 300 through the filter circuit 720, the anti-interference ability of the first voltage can be improved.

[0077] In summary, the present application outputs a first square wave signal according to the detection signal of the first capacitor plate 110 and the third capacitor plate 130 through the multi-frequency oscillation circuit 200, and outputs a second square wave signal according to the detection signal of the second capacitor plate 120. When no foreign matter is detected, the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit 200 are calibrated by the control circuit 400. After calibration, the logic gate circuit 300 outputs a first voltage according to the first square wave signal and the second square wave signal. The control circuit 400 determines whether there is a foreign matter in the building 101 based on the first voltage and the preset voltage threshold, thereby realizing accurate detection of non-ferrous foreign matter such as plastic water pipes and wooden beams in the building 101.

[0078] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0079] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A building detection device, characterized in that: include: A first capacitor plate (110), a second capacitor plate (120), a third capacitor plate (130), a multi-frequency oscillation circuit (200), a logic gate circuit (300) and a control circuit (400); The first capacitor plate (110), the second capacitor plate (120) and the third capacitor plate (130) are arranged at intervals in the horizontal direction; the output end of the first capacitor plate (110), the output end of the third capacitor plate (130), the first end of the control circuit (400) and the first end of the multi-frequency oscillation circuit (200) are connected in common; the output end of the second capacitor plate (120) is electrically connected to the second end of the multi-frequency oscillation circuit (200); the first end of the logic gate circuit (300) is electrically connected to the third end of the multi-frequency oscillation circuit (200); the second end of the logic gate circuit (300) is electrically connected to the fourth end of the multi-frequency oscillation circuit (200); and the third end of the logic gate circuit (300) is electrically connected to the second end of the control circuit (400); The multi-frequency oscillation circuit (200) is used to output a first square wave signal according to the detection signals of the first capacitor plate (110) and the third capacitor plate (130), and to output a second square wave signal according to the detection signal of the second capacitor plate (120); when no foreign matter is detected, the control circuit (400) is used to calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit (200); after calibration, the logic gate circuit (300) outputs a first voltage according to the first square wave signal and the second square wave signal; and the control circuit (400) is used to determine whether a foreign matter is present in the building (101) according to the first voltage and a preset voltage threshold.

2. The building detection device according to claim 1, characterized in that: The control circuit (400) is used to compare the first voltage with the preset voltage threshold; If the first voltage is greater than the preset voltage threshold, it is determined that a foreign object exists in the building body (101) corresponding to the second capacitor plate (120).

3. The building detection device according to claim 1, characterized in that: The control circuit (400) is used to calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit (200), which means: The control circuit (400) is used to output a bias voltage, and based on the bias voltage, adjust the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit (200), so that the first square wave signal and the second square wave signal are complementary.

4. The building detection device according to claim 1, characterized in that: The control circuit (400) is further used to obtain a plurality of the first voltages within a preset period and calculate a real-time variance of the plurality of the first voltages, and determine the preset voltage threshold based on the real-time variance and a fixed offset.

5. The building detection device according to claim 1, characterized in that: Also includes: A detection antenna (500), used for detecting a charged conductor and outputting a detection signal; an amplifying circuit (600), electrically connected to the detection antenna (500) and the third end of the control circuit (400), respectively, and configured to amplify the detection signal and output the amplified signal to the control circuit (400); The control circuit (400) determines whether there is a charged conductor in the building (101) based on the amplified detection signal.

6. The building detection device according to claim 5, characterized in that: The control circuit (400) calculates the amplitude according to the amplified detection signal and compares the amplitude with a preset amplitude threshold. If the amplitude is greater than the preset amplitude threshold, it is determined that a charged conductor exists in the building (101) corresponding to the current building detection device.

7. The building detection device according to claim 5, characterized in that: The amplifier circuit (600) comprises: A capacitor (610), wherein a first end of the capacitor (610) is electrically connected to the detection antenna (500); an amplifier (620), wherein a first end of the amplifier (620) is electrically connected to a second end of the capacitor (610), and a second end of the amplifier (620) is electrically connected to a third end of the control circuit (400); a first resistor (630), wherein a first end of the first resistor (630) is connected in common with a first end of the amplifier (620) and a second end of the capacitor (610), and a second end of the first resistor (630) is electrically connected to a second end of the amplifier (620); and A bias circuit (640), wherein a first end of the bias circuit (640) is used to be electrically connected to a power supply (601), a second end of the bias circuit (640) is electrically connected to a third end of the amplifier (620), and a third end of the bias circuit (640) is grounded.

8. The building detection device according to any one of claims 1 to 7, characterized in that: The control circuit (400) comprises: a bias generator (410), wherein a first end of the bias generator (410) is commonly connected to an output end of the first capacitor plate (110) and an output end of the third capacitor plate (130), and is used to output a bias voltage, and calibrate the first square wave signal and the second square wave signal output by the multi-frequency oscillation circuit (200) based on the bias voltage when no foreign object is detected; and A controller (420), wherein a first end of the controller (420) is electrically connected to a second end of the bias generator (410), and a second end of the controller (420) is electrically connected to a third end of the logic gate circuit (300), and the controller (420) is used to determine whether a foreign object exists in the building (101) based on the first voltage and a preset voltage threshold.

9. The building detection device according to any one of claims 1 to 7, characterized in that: Also includes: A second resistor (111), wherein a first end of the second resistor (111) is connected to an output end of the first capacitor plate (110) and an output end of the third capacitor plate (130), and a second end of the second resistor (111) is electrically connected to a first end of the multi-frequency oscillation circuit (200).

10. The building detection device according to any one of claims 1 to 7, characterized in that: Also includes: A third resistor (121), wherein a first end of the third resistor (121) is connected in common with an output end of the second capacitor plate (120), and a second end of the third resistor (121) is electrically connected to a second end of the multi-frequency oscillation circuit (200).

11. The building detection device according to any one of claims 1 to 7, characterized in that: Also includes: An alarm (710) is electrically connected to the fourth end of the control circuit (400).

12. The building detection device according to any one of claims 1 to 7, characterized in that: Also includes: A filter circuit (720), wherein a first end of the filter circuit (720) is electrically connected to a third end of the logic gate circuit (300), and a second end of the filter circuit (720) is electrically connected to a second end of the control circuit (400).

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