SU1322145A1 - Device for quality control of structural articles - Google Patents

Abstract

The invention relates to the field of construction, in particular to the quality control of products by the resonant method. It is intended to diagnose the quality of building structures and products both from metal and from non-metals, which allows to increase the accuracy of control. The device contains emitter 1, which is used as a 10GD-34 loudspeaker, receiver 2, which is used as an accelerometer sensor KD-10, amplifier 3, first detector 4, low-pass filter 5, second detector 6, comparator 7, waiting for a multivibrator 8, generator 9, power amplifier 10, frequency meter 11 with digital indication, power supply unit 12, measuring device 13 (digital voltmeter) and product 14. 2 Il. I (ft ft. 1

Description

The invention relates to the field of construction, in particular, to quality control of products using a resonant method and is intended to diagnose the quality of building structures and products both from metals, as well as from non-metals, when it is important to determine the physical and mechanical characteristics of products with sufficient accuracy, to vibrate them in the process of operation.

The purpose of the invention is to increase the accuracy of the control.

FIG. 1 shows a device for controlling the quality of building products; FIG. 2 is a diagram of the operation of the device.

The device contains a 1 "emitter. 10GD-34 loudspeaker, 2 receiver, KD-10 accelerometer sensor, amplifier 3, detector 4, low pass filter 5, detector 6, comparator 7, multivibrator 8, a generator 9, a power amplifier 10, a frequency meter 11 with a digital indication, a power supply unit 12, a measuring device 13 for measuring the amplitude and a test article 14,

 The electrical signal in the device circulates in a closed circle, and its frequency can vary in two modes: manually and automatically.

The device for controlling the quality of building products works as follows.

The receiver 2 is attached to the product 14 at the location where the maximum amplitude is assumed to occur when the product oscillates. When the device is turned on, the generator produces an electrical signal of variable frequency (Fig. 2, a). This electrical signal is amplified by the power amplifier 10 and converted into acoustic oscillations by the emitter 1, which acts on the ICT) 14. The receiver 2 converts the mechanical oscillations of the product 14 into an electrical signal that goes to the amplifier 3, amplifies and is fed to the input of the detector 4. The input signal is a high-frequency filling and a low-frequency envelope (Fig 2, b). To reduce the low-frequency envelope, a detector is included in the circuit, from the output of which a detected

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a signal (Fig. 2, c), and a low-pass filter, from the output of which a low-frequency envelope is obtained (Fig. 2, d). A low-frequency envelope enters the peak detector and the input B of the comparator. The comparator's input A receives the output signal from the peak detector (Fig. 2e). The comparator is switched on to compare the signals at inputs A and B. As the amplitude of oscillation of the product 14 increases, this happens when the frequency of forced oscillations oscillates to the natural frequency of the product , the signal at the input 5 of the detector (Fig. 2, e) increases, the potential at the input B of the comparator is greater than or equal to the potential at the input A. At the same time, the output of the comparator will be a positive potential (figure 2, g). After passing through the mechanical resonance frequency, the potential at input B of the comparator becomes less than the potential at input A. At the output of the comparator, a potential of zero appears. The level difference at the comparator output is triggered by a standby multivibrator, which produces a pulse with a duration (FIG. 2, g). This pulse starts a frequency meter that measures the frequency of the input signal.

The proposed device allows controlling the characteristics of natural oscillations in hard-to-reach places and in field conditions.

Claims (1)

Invention Formula A device for quality control of building products containing an emitter and a receiver that is connected to one amplifier input, to another input of which a power source is connected, the amplifier output is connected to the frequency counter input, one measuring unit input and the first detector input, the first detector output is connected to the input low pass filter, one output of which is connected to another input of the measuring unit, generator and power amplifier, which is due to the fact that, in order to improve the control accuracy, it is equipped with eye Detector, comparator and multivibrator waiting, and another output of the low-pass filter is connected to the input of the second detector and one input of the comparator, the output of the second detector is connected to another input of the comparator, the output 0 0 45 0 five 313221454 whose output is connected to the input of the generator to the input of the generator, which is connected to the multivibrator, the outputs are frequency measured through a power amplifier to the electric and waiting multivibrator connected to the reader. but w and i / Compiler A.Kuznetsov Editor S.Patrusheva Tehred A.Kravchuk Proofreader A.T. Order 2856/39 Circulation 776 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Design, 5 g