SU1061041A1 - Device for measuring rate of impact wave propagation in materials - Google Patents

Abstract

A DEVICE FOR MEASURING THE SPEED OF SPEED WAVE WAVES IN MATERIALS, containing an electrodynamic drummer, a receiver, an amplifier connected in series and a threshold circuit, a generator of the measured time interval and a digital clock device, which differs from the fact that, in order to increase control format, it is provided with a controllable divider connected between the receiver and amplifier, a divider control circuit, the output of which is connected to the second input of the controlled divider, are serially connected and a key and control key control circuit, the key control circuit input is connected to the second output, a threshold circuit connected in series by the second driver of the measured time interval and a digital reading device, the output of the controlled switch is connected to the first input of the second driver of the measured time interval, the second input the controllable key and the input of the control circuit of the divider are connected to the first output n (P) of the standard circuit, (L and the second inputs of both drivers of the measured time interval connected with electrodynamic drummer.

Description

1. The invention relates to non-destructive testing methods of materials and can be used in construction. A device for measuring the velocity of propagation of shock waves in materials is known, in which the automatic measurement of the velocity of the longitudinal: 1x waves with a digital readout 1 is provided. However, it does not provide the possibility of determining the velocity of surface waves. The closest to the technical essence of the invention is a device for measuring the velocity of propagation of impact waves in materials, containing an electrodynamic drummer, a receiver, a series-connected amplifier, a threshold circuit, a former time meter, and a digital reading device 2. The disadvantage of the known device is also; the inability to determine the speed of surface waves. The purpose of the invention is to increase the information content of the control. The goal is achieved by the device dp measuring the velocity of propagation of impact waves in materials, containing an electrodynamic drummer, a receiver, successively connected amplifier and threshold circuit, a former time meter, and a digital reading device, with a gabgen controlled divider connected between the receiver and an amplifier, a divider control circuit, the output of which is connected to the second input of a controlled divider, are serially connected by a key control circuit and controlled with a key, the input of the key control circuit is connected to the second output of the threshold circuit, connected in series by the second driver of the measured time interval and a digital reading device, the output of the controlled key is connected to the first input of the second driver of the measured time interval, the second input of the controlled key and the input of the divider control circuit is connected to the first output of the threshold circuit, and the second inputs of both drivers of the measured time interval are connected to the electrodynamic drummer. FIG. 1 is a block diagram of a device for measuring the velocity of propagation of shock waves in materials; in fig. 2 - timing diagrams for the operation of the device. The device contains a drummer 1. receiver 2, a successively connected suppressor 3 and a threshold circuit 4, the first shaper 5 of the measurable time source and the digital reading device 6, a divisible divider 7 connected between the receiver 2 and the amplifier 3, the divider control circuit 8, the output 1 of which is connected to the second input of the controlled divider 7, the key control circuit 9 and the control key 10 are connected in series, the input of the key control circuit 9 is connected to the second output of the threshold circuit 4, serially connected. worlds 11 of the measured time interval and a digital reading device 12, the output j of the control key 10 is connected to the first input of the second formrivate 1.1 of the measured time interval, the second input of the control key 10 and the input of the divider control circuit 8 is connected to the first output of the threshold circuit 4, and the second inputs of the first 5 and second 11 drivers of the measured time interval are connected to the electrodynamic drummer 1. The device operates as follows. In the initial state, the controlled divider 7 has the maximum transmission coefficient, and the controlled key 10 is locked and locks the first input of the former 11 of the measured-time interval. After striking the imp. from the electrodynamic impactor (Fig. 2a) enters the formers 5 and 11, the measured interval, which provides the beginning of the counting time, and the shock waves propagate in the material - longitudinal, having a maximum speed, and surface speed, which is approximately 1, 9 times less than the speed of the longitudinal wave. Therefore, the front of the longitudinal wave first comes to receiver 2, and then, after some time, the surface wave front, whose amplitude is I times larger than that of the longitudinal wave (the value of I increases with increasing sound base, since the energy of surface waves decreases in proportion to the distance 1 and longitudinal waves are proportional to the square of this distance). The electrical oscillations (Fig.) Converted by the receiver 2 through the controlled divider 7 and the amplifier 3 are fed to the input of the threshold circuit 4. The leading edge of the pulse of this circuit is generated at the threshold. the voltage Ug (Fig. 2c) is applied to the shaper 5 of the measured time interval, after which the value of the propagation time of the longitudinal wave (Fig. 2 h) is counted and displayed on the digital reading device 6. The leading edge of the pulse from the output of the threshold circuit 4 is started a divider control circuit 8, generating a pulse (Fig. 2 g), arriving at the second input of the controlled divider 7. The transmission coefficient of the latter decreases sharply, respectively. the level of the signal at the output of amplifier 3 decreases (Fig. 2e). The threshold for the SM4 .4 will work further from the leading edge of the surface wave (Fig. 2 e). By this time, the control key 10 opens, since its first input from the output of the key control circuit 9 is given a trigger pulse (FIG. 2d). 5 The key control circuit 9 is triggered by the falling edge of the threshold circuit 4 (FIG. 2). ) to ensure that the condition of unlocking the controlled key 10 is satisfied after the transfer ratio 10 of the controlled divider 7 has decreased, the leading edge of the pulse of the threshold circuit 4 (FIG. 2) goes to the second input of the imaging unit 11 of the measured time interval, after which

the value of the propagation time of the surface wave (Figs. 2 and 2) is measured and measured on the digital reading device 12,

After the end of the measurement cycle of the circuit 8-9, the control of the divider and key is removed. control voltages from the controllable divider 7 and the control key 10, drive them to their original state.

The use of the device allows the automatic simultaneous measurement of the propagation velocity of the longitudinal and surface waves, which increases the information content of the control.

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Claims (1)

DEVICE FOR MEASURING THE SPEED OF SPREAD OF WAVE OF IMPACT In MATERIALS, containing an electrodynamic drummer, a receiver, a serially connected amplifier and a threshold circuit, a shaper of the measured time interval and a digital readout device, which is related to the fact that, in order to increase the information content of the control, it equipped with a controlled divider connected between the receiver and the amplifier, a divider control circuit, the output of which is connected to the second input of the controlled divider, connected in series with the key control circuit and the controlled key, the input of the control circuit the key is connected to the second output of the threshold circuit, connected in series with the second shaper of the measured time interval and a digital reading device, the output of the controlled key is connected to the first input of the second shaper of the measured time interval, the second input of the controlled key and the input of the divider control circuit § are connected to the first output threshold circuit, and the second inputs of both formers of the measured time interval are connected _ £, with an electrodynamic hammer.