SU469082A1 - Automatic Defect Alarms - Google Patents

Description

one

This invention relates to the field of ultrasound quality control of products in metallurgy and mechanical engineering.

Automatic defect signaling devices are known, comprising a synchronizer, a time selector, a counter, an anti-coincidence circuit, a controller for the number of recorded impulses from defects, and a recorder. A cumulative counter is used as a regulator of the number of pulses that trigger the recorder.

However, these alarms have limited operating pulse frequencies, the accuracy of the operation is influenced by pulsed interference, there is no echo signal from a defect in any of the steps of the flaw detector operation.

The proposed signaling device differs from the known ones in order to improve noise immunity, it is provided with a generator connected to one of the inputs of the driver and connected in series with each other by a delay generator, a strobe pulse generator and a matching circuit, the second input of the matching circuit is connected to the second output of the driver. by the registrar.

FIG. 1 shows the block diagram of the proposed detector; in fig. 2 - time diagrams.

The detector contains a generator of control zone 1, triggered by a sync pulse of flaw detector 2, a temporary selector 3, to which video signal 4 is supplied from the output of the flaw detector amplifier. The second input of the selector 3 is connected to the output of the generator of the control zone 1, and its output is connected to the input of the imaging unit 5, its output connected simultaneously with the inputs of the delay generator 6

and the matching circuit 7. The output of the delay generator 6 is connected to the input of the generator of the strobe pulse 8, connected by its output to the second input of the matching circuit 7, the output of which goes to the input of the recorder 9.

The sync pulse from the flaw detector synchronizer 2 arrives at the input of the generator of the control zone 1, and the signals from the amplifier of the flaw detector come to the input of the temporary selector 3. At the output of the collector 3, a sequence of echo signals from the defect is extracted using the gating pulse of the control zone generator, which are normalized in amplitude and duration on the shaper 5 (see Fig. 2a). These pulses trigger the delay generator 6, generating a rectangular pulse of adjustable duration (see Fig. 26), and also arrive at one of the inputs of the coincidence circuit 7. A trailing edge of the rectangular pulse triggers the gate pulse generator 8, which produces a square pulse (see Fig. 2c), which is fed to the second input of the coincidence circuit, i.e., depending on the pulse duration of the delay generator, the gating pulse may be delayed by 2, 3 and a different number of pulses from defects. Therefore, at the output of the coincidence circuit 7, a pulse appears (see Fig. 2 d), delayed by the corresponding number of the pulse following period from the defect.

The occurrence of impulse noise in any period of the pulse from the defect, which triggers the delay generator, and then the temporary loss or decrease of its level, does not reflect on the operation of the alarm device, and a signal appears on its output about the presence of a defect.

If there is no signal from a defect and the appearance of a pulsed disturbance in the receiving path of the flaw detector, only the delay generator is triggered, and the likelihood of a strobe pulse and a secondary interference pulse is very small. In this case, the recorder does not signal the presence of a defect.

Subject invention

An automatic defect signaling device containing a generator connected in series, a time selector, an echo pulse generator, and a recorder, characterized in that, in order to improve the noise immunity of the signaling device, it is provided connected to one of the driver's inputs and connected in series with each other by a delay generator, a strobe pulse generator, and the matching circuit, the second input of the matching circuit is connected to the second output of the driver, and the output of the circuit to the recorder.