JPS5831260Y2 - Concrete failure detection device - Google Patents

Description

[Detailed explanation of the invention] This boundary plan embeds a vibration detection element such as a piezoelectric element 2 in or places it in contact with a concrete structure such as a wall 1-, a floor, and a ceiling, and outputs the output of this vibration detection element. are input to the detection voltage input terminals of the high level detector 3 with a high detection level and the low level detector 4 with a low detection level, respectively, and to the appropriate voltage terminals of a voltage dividing resistor circuit 6 in which a variable resistor 5 is inserted in series. The comparison voltage input terminals of the above-mentioned low level detector 3 and low level detector 4 are connected, and when the low level detector 3 outputs a predetermined number of times, or This is a concrete destruction detection device that outputs a destruction detection signal when an output occurs continuously for a predetermined period of time, and its purpose is to detect concrete destruction by illegal intruders based on different methods To provide a concrete fracture detection method which improves detection sensitivity, prevents malfunctions, improves detection accuracy, and simplifies adjustment work to reduce costs by changing the method.

When an intruder breaks into a concrete structure such as a general Nikon concrete wall, floor, or ceiling, two methods are used: by hitting a chisel with a hammer, and by using an electric drill. It is possible to destroy the material by drilling it with a drill such as this.

According to these experiments, in the former case, concrete structures were found to undergo intermittent repetition of relatively large, very short-term vibrations, while in the latter case, concrete structures were found to undergo relatively long, continuous vibrations at a relatively low level. It was recognized that it occurs over time.

゛ □ , □・The present invention was developed with the above-mentioned points in mind, and is used for detecting chisel breakage. Destruction detection is performed individually by measuring the continuous time of the level detector output, and is adapted to the methods of both gun and drill destruction, respectively. .

An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a schematic diagram of an embodiment of the present invention, and 2 in the figure is a piezoelectric element embedded in a wall 1 made of Yonkrete as a vibration detection element, Detect vibrations of a concrete structure such as wall 1.

Reference numeral 11 denotes an amplification circuit for amplifying the output of the piezoelectric element 2, and the outputs of the amplification circuits 11 and 11 are respectively connected to the high level detector 3.
is input to the low level detector 4.

The high level detector 3 has a detection level L1, and detects only the output signal of the amplifier circuit 11 having a high peak value that occurs when a chisel breaks as shown in A in FIG. The level detector 3 is configured to generate an output pulse signal as shown at the beginning of Figure 2.The output pulse signal of the high level detector 3 is waveform-shaped by the waveform shaping circuit 12 and then sent to the counting circuit 7. When the input pulse signal is generated a predetermined number of times, the count circuit 7
A signal is sent to the output circuit 8 to perform a destruction detection operation.

On the other hand, the low level detector 4 is the high level detector 3.0.
The output signal of the amplification circuit 11, which has a detection level L2 lower than that of the case, and which is continuous at a relatively low level as shown in B of FIG. By inputting the output signal of 4 to the integrating circuit 9, an output waveform as shown in FIG. 2 is generated in the integrating circuit 9.

Therefore, the output circuit 8 detects the output waveform of the integrating circuit 9 as shown in FIG. 2 at the output level L3, generates an output signal as shown in FIG. 2, and performs a destruction detection operation.

FIG. 3 shows a specific circuit example of the embodiment of the present invention, in which 2 is a piezoelectric element, 11 is an amplification circuit, and the amplification circuit 11 includes an input field effect transistor FET and a transistor Tri.
It is composed of.

3.4 is a high level detector and a low level detector respectively composed of operational amplifiers ■C1 and ■C2, and as shown enlarged in FIG. 4, a variable resistor 5 and resistors R1 and R2 are connected in series. Connect the comparison voltage input terminal of the operational amplifier ■C1 of the noise level detector 3 to the connection point between the variable resistor 5 and the resistor R1 of the voltage dividing resistor circuit 6 obtained by connecting the resistor R1 and the resistor R1. R
The operational amplifier IC2 of the low level detector 4 is connected to the connection point with 2.
The comparison voltage input terminal of is connected, and both arithmetic amplifier ■C1
The detection voltage input terminals of the IC2 are commonly connected to the output terminal of the amplifier circuit 11.

As a result, the operational amplifier I of each level detector 3, 4
It is possible to change the detection level voltage applied to the comparison voltage input terminal of C1+IC,2 by a constant upper limit (R1-1-Rz:Rt) by simply changing the resistance value of the variable resistor 5. The detection levels of both level detectors 3 and 4 can be adjusted by adjusting the variable resistor 5.

Next, the output of the high level detector 3 is inputted to the counting circuit 7 via the waveform shaping circuit 12 constituted by the operational amplifier IC3.

The output of the switched low level detector 4 is input to an integrating circuit 9 composed of a capacitor C8 and an operational amplifier IC5.

8 is an output circuit, which is composed of an operational amplifier IC6 and a transistor Tr2, and the output of the integrating circuit 9 and the output of the counting circuit 7 is connected to a diode])1. , D2, and when this input signal level exceeds the output level L3, the transistor Tr2 is cut off and the output is low.
At the same time, the light emitting diode LED is turned off, and destruction detection operation and display are performed.

In the figure, numeral 10 is a constant voltage power supply circuit composed of a transistor Tr3 and a Zener diode ZD, and ZNR is a switching element for removing surge.

FIG. 5 shows a conventional example of the input part of both level detectors 3 and 4 of the present invention, and in the case of a device with two detection levels, the operational amplifier I of both level detectors 3 and 4 is shown. Ci,
Since different detection level voltages must be applied to the comparison voltage input terminals of IC2, separate variable resistors 1 are required for each.
3.14 to the comparison voltage input terminal to each operational amplifier I.
The detection level voltage of C11IC2 is set by each variable resistor 13.
．． 14 and adjusted individually.

However, in such a conventional example, the variable resistor 13.1
4 is required, resulting in disadvantages such as increased cost, increased size due to expanded installation space, and troublesome adjustment work.

The present invention has been proposed in view of this point, and as described above, the output of the vibration detection element is connected to the detection voltage input terminals of a high level detector with a high detection level and a low level detector with a low detection level. Connect the comparison voltage input terminals of the high level detector and low level detector mentioned above to the appropriate voltage terminals of the voltage dividing resistor circuit with a variable resistor inserted in series. Comparison with a level detector It is possible to change and adjust each detection level voltage applied to the voltage input terminal at a constant Q ratio by simply changing the resistance value of one variable resistor. This has the advantages of reducing the installation space, simplifying the circuit configuration, lowering manufacturing costs, and simplifying the adjustment of the detection level voltage. and input the output of this dynamic ejection element to a noise level detector with a high detection level and a low level detector with a low detection level,
・Conc'J
-1- It is possible to adopt a detection method that is compatible with the methods of concrete destruction, whether a structure is destroyed with a chisel or a structure with a drill,
It has the advantage of being able to reliably detect both chisel breakage and drill breakage, and to easily eliminate causes of malfunction due to noise, etc. This has the advantage of improving detection accuracy, preventing malfunctions, and making it possible to detect destruction of concrete structures with high reliability.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2 A, C, and 2 are explanatory diagrams of the same operation, Fig. 3 is a side view of the same concrete circuit, and Fig. 4 is the main part of the same. The enlarged circuit diagram, FIG. 5, is a circuit diagram of the same conventional example as above, where 1 is a wall, 2 is a piezoelectric element, and 3 is a...
- 4 is a low level detector, 5 is a variable resistor, and 6 is a voltage dividing resistor circuit.

Claims (1)

[Scope of utility model registration request] A vibration detection element such as a piezoelectric element is embedded in or placed in contact with a concrete structure such as a wall, floor, or ceiling, and the output of this vibration detection element is divided into high-level detectors with a high detection level and low-level detectors with a low detection level. Connect the pie level detector and low level detector stop comparison mass production/input terminals to the appropriate voltage terminals of a voltage dividing resistor circuit in which a variable resistor is inserted in series while inputting each to the detector stop detection voltage input terminal, and... A cosiclete destruction detection device which outputs a destruction detection signal when a high level detector outputs a predetermined number of times or when a low level detector outputs continuously for a predetermined period of time.