SU1523962A1 - Centrifugal installation for impact tests of specimens - Google Patents

Abstract

The invention relates to the testing of materials, in particular to centrifugal installations for impact testing of specimens for strength. The purpose of the invention is to expand the functionality by providing tests not only in static loading mode to failure, but also multiple shock loading with a constant force, as well as forces of various sizes, including stepwise varying, with full unloading of the sample between loads. . The installation comprises a platform 4 mounted on the shaft 2 of the actuator 3, and a mechanism for moving the grippers 6, 7 of sample 8 relative to the axis of rotation of the platform, including a rotating drum 11, a gear rack 13 and a gear wheel 14, in which slot 17 the grippers and associated with them weights 9, 10, and flexible pull 15. Sample loading is performed by moving the wheel 14 along the guide 5 when moving loads 9, 10 along the groove 17, and unloading occurs when the axis of the grips is parallel to the axis of rotation of the platform. 1 il.

Description

flexible pull 15. Step-loading of the specimen is done by moving the wheel 14 along the guide

the groove 17, and the unloading takes place when the axis of the grippers is located parallel to the axis of rotation of the platform.

5 when moving loads 9, 10 along 1 Il.

The invention relates to testing materials, in particular to centrifugal installations for impact testing of specimens for strength.

The aim of the invention is to expand the functionality by providing tests not only in the static loading mode to failure, but also multiple shock loading with both constant force and forces of various sizes, including stepwise varying, with full unloading of the sample between loads. .

The drawing shows the installation diagram, a general view.

The installation includes a housing 1, a vertical shaft 2 installed therein with a drive 3 of its rotation, a platform A with a radial guide 5 attached to the shaft 2, grips 6 and 7 of sample 8, loads 9 and 10, fitted with the possibility of interaction with corresponding grippers , and the mechanism for moving the grippers with respect to the axis of rotation of the platform 4, the engaging drum 1 1 with a 12 rotation drive, toothed rack 13 and the wheel 14, and a flexible rod 15, an envelope wheel 14, one end of which is fixed to the drum 11 and the other (end 16 ) -on platform 4.

A toothed rack 13 is mounted along a guide 5, a toothed wheel 14 is provided with a diagonal groove 17 in which grippers 6 and 7 and weights 9 and 10 are installed, and with a groove on the toothed surface in which the bend is stretched 15 ha so that not prevent the wheel from engaging the rail. For the same purpose, an additional drum mounted on the gear wheel axis (not shown) can be used. Cargo 18 balances platform 4.

The installation works as follows.

Set the wheel 14 in position, in which the axis of the grippers 6 and 7

parallel to the axis of rotation of the platform 4 (position shown; ia of the drawing) and turn on the drive 3. The rotation speed of the platform is adjusted to the preset and the drum 11 is set to rotate. The load ha 15 unwinds from the drum 11, the length of the loop enveloping wheel 14 increases 14 moves along the rail 13, rotating around its axis. When the wheel turns, loads 9 and 10 cyclically move the grippers 6 and 7 with sample 8 along groove 17 and load the sample with impact loads with increasing force of impact due to an increase in the radius of rotation of loads 9 and 10 as the wheel moves along guide 5. When turning, the wheel 14 periodically takes a position in which the axis of the grippers becomes parallel to the axis of rotation of the platform. At this position, the centrifugal force of the weights 9 and 10 is perceived by the walls of the groove 17 and the sample 8 is completely unloaded. There is a stepwise increase in shock load with sample unloading between shocks. The frequency of the load is controlled by the drive 12 by changing the speed of rotation of the drum I1, the total level of loads is determined by the speed of rotation of the platform 4.

With unequal weights of loads 9 and 10, the adjacent pulses in the cycle have different values. In the absence of a gap between the loads 9 and 10 and the ends of the groove 17, the tests are carried out with a static increase in load on the steps, without impacts. By rotating the drum 11 in different directions, two-cycle loading is obtained due to the reciprocating movement of the wheel 14 along the driving 5.

Claims (1)

Invention Formula A centrifugal unit for percussion testing of samples, comprising a housing, a shaft installed in it with a drive for its rotation, a platform mounted on the shaft with a radial 51 two two grippers for the sample, loads that are capable of interacting with the respective grippers, and a mechanism for moving the grips relative to the axis of rotation of the platform, including a drum with a rotational drive and fixed on it at one end a flexible pull, characterized by that, for the purpose of expansion, neither functionality by providing tests not only in static loading mode before destruction, but also in a stepped impact 239626 With the full mode of unloading the sample between the loads, the mechanism for moving the grippers includes a gear pair consisting of a wheel and a rail mounted along the guide, the wheel is mounted for movement along the rail and in it, there is a diagonal groove in which Q clamps and corresponding weights are installed, and a groove on the side surface is designed to accommodate a flexible rod that bends around the wheel, and its other end is fixed 15 on the platform.