SU1597688A2 - Apparatus for detecting defects in materials - Google Patents

Abstract

The invention relates to a testing technique and is an improvement of the known device described in the author. N1262341. The purpose of the additional invention is to increase the sensitivity by increasing the signal from the rebound speed sensor of the impactor. The drummer strikes the handpiece in contact with the test object with the frequency of the alternating current source. The impactor speed of the impactor is measured by an electromagnetic sensor connected to the impactor by a rod. The ferromagnetic cap, which is rigidly connected to the rod and the permanent magnet of the sensor, increases the signal from the sensor, since the measurement is carried out at the moment when the cap is detached from its fixed magnetic circuit. 2 Il.

Description

The invention relates to: testing equipment and is an improvement of the known device according to the author.

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The purpose of the invention is to increase sensitivity by increasing the signal from the rebound speed sensor of the impactor.

Fig. 1 shows a device for detecting defects in materials; Fig. 2 shows a drum rebound speed sensor.

A device for detecting defects in materials comprises a housing 1, a hammer located therein 2 with a rod 3, a spherical segment tip 4 in the form of a spherical segment facing the hammer 2 and a flat to the surface of the test object 5, a solenoid 6 fixed in housing 1 coaxially the striker 2 and connected via diode 1 to the AC source 8, an electromagnetic sensor 9 of the rebound speed of the striker 2 fixed in the housing 1 ,. containing a coil 10 connected through a peak detector 11 with a registering device 12 a permanent magnet 13 and a return spring 14. The tip 4 is attached to the case 1 by screws 15 through elastic gaskets, between the sensor 9 and the hammer 2 there is a resilient stop 16.

The ferromagnetic cap 17 is rigidly connected to the rod 3 and the permanent magnet 13.

The rod 3 is structurally of such length that, at maximum force, the interaction of the striker with tip 4 has a minimum gap between the surface of the cap 17 and the magnetic core 9.

The device works as follows.

When the AC source 8 is connected, a solenoid b is turned on, which is attracted to the impactor 2, compresses the return spring 14. At this moment, because of the diode 7 which passes only one half wave

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alternating current, the solenoid 6 is turned off for half the period of alternating current. Under the action of the return spring 14, the striker strikes tip 4 and bounces off it with a certain speed. During the rebound, the ferromagnetic cap 17 connected to the permanent magnet 13 moves away from the fixed magnetic circuit of the electromagnetic sensor 9 of the rebound speed of the impactor 2. At the moment of mechanical detachment of the ferromagnetic cap 17 connected to the permanent magnet 13, a maximum EMF is induced from the fixed magnetic circuit. Signal through peak

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the detector 11 enters the recording device 12. The cycle is repeated.

The magnitude of the rebound of the impactor 2 depends on the physico-mechanical properties of the test material, on the presence of defects in it.

Formula of the Invention A device for detecting defects in materials is automatically modified. No. 1262341, differing from the fact that, in order to increase the sensitivity, it is equipped with a ferromagnetic cap, rigidly connected with the rod and the permanent magnet of the electromagnetic speed sensor ,.

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Claims (1)

Claim Device for determining defects in materials No. 1262341, distinguished by the fact that, in order to increase sensitivity, it is equipped with a ferromagnetic cap rigidly connected to the rod and a permanent magnet of the electromagnetic speed sensor .. FIG. 1 Editor A. Shandor Compiled by I. Khodataev Tehred M. Morgenthal Corrector S. Sheckmar Order 3047 Circulation 499 Subscription? VNIIIPI State Committee for Inventions and Discoveries under the State Committee for Science and Technology of the USSR 113035, Moscow, Zh-35, Raushskaya nab ,, 4/5 Production and Publishing Combine Patent, Uzhgorod, 101 Gagarin St.