SU813159A1 - Test-bed for testing articles for shock - Google Patents

Description

I

The invention relates to the inceptive technique, in particular, to stands for testing products for the impact of a single shock load.

A stand for testing products for impact is known, comprising a pressure chamber in which a piston is installed with a rod interacting with the product under test, a pressure source from a ruptured membrane connected to the chamber and a stroke stop made in the form of an annular element with a screw slot and shear pin entering into it, fixed on rod ll.

The disadvantage of this stand is the additional shock that precedes the main one during the shearing of the pin and the complexity of the structures.

The closest to the technical essence of the invention is a stand (Y test, with an oil chamber containing a pressure chamber, a free-standing head, and in one of these

elements are made of pressure relief holes ol the chamber at a predetermined displacement of the striker, one hundred to secure the test object, equipped with a head impacting with the impactor, and means of restraint of the impactor in the original wake. The acceleration of the striker is carried out at a lower pressure in the chamber. When the striker strikes the anvil of the table, the valve, which closes the air to the pressure-relief openings made in the striker, opens under the action of inertial villages, overcoming the force of the valve springs and the pressure in the chamber drops sharply, which eliminates the possibility of anvil l2.

The disadvantage of this stand is the design complexity and lack of reliability associated with the presence of a valve triggered by inertial forces.

The purpose of the invention is to simplify the design and increase reliability.

3e

The goal is achieved by the fact that the holes for pressure relief are made in the chamber.

In addition, the table can be made in the form of a beam, the ends of which are installed in mobile supports.

FIG. 1 given stand, general view; in fig. 2 is a section A-A of FIG. one.

The bench contains a pressure chamber 1 in which the firing pin 2. is freely installed. The means for keeping the striker 2 in the initial position are made in the form of stops 3. A pressure source 4 is connected to the chamber 1, separated from it by a destructible membrane 5. There are holes 6 in the walls of the chamber 1, with which the cavity 7 of the chamber 1 starts communicate with the atmosphere. Camera 1 is installed with a gap in relation to the anvil 8, mounted on the bottom surface of the table 9, through the gasket 1O. A test article 11 is mounted on a table 9, made in the form of an elastic beam, the ends of which are fixed in movable supports. The movable supports can be made, for example, in the form of guides 12 rigidly fixed to the base 13 and supports 14, which can be fixed in various places of the guides 12 using staples 15 and clamps 16.

The stand works as follows.

In the initial position shown in the drawing, a shock wave is created by breaking the membrane 5 under the action of high pressure. Head 2 is mixed in chamber 1 and strikes an anvil 8, transmitting a shock pulse through gasket 10 and table 9 to test article 11. At the moment of impact, head 2 is higher than chamber 6 in chamber 1, through which compressed air escapes to atmosphere, preventing repeated blows striker 2 of the anvil 8. Under the impact of the shock pulse received from the striker 2, the table 9 experiences natural oscillations which, due to external resistances, as well as internal friction in the material, fade out. Characteristics of the shock im-

159.4

The pulse varies due to the pressure change in the pressure source 4 and in -. exchange of destructible membranes 5, the thickness of the interchangeable table 9, the selection of the material of the table (various elastic moduli of the material) and its length between the supports. The gap between chamber 1 and the anvil 8 is selected so that the firing pin 2 returns to the supports 3 after the impact. The material and thickness of the gasket under the anvil are chosen so that the impact time of the striker on the anvil is less than half of the required shock pulse duration.

15- The described wall eliminates the possibility of additional shocks, allows you to create loads close to real, provides high reliability of operation due to simplicity

20 of all design elements.

Claims (2)

1. Stand for testing products on a blow containing a pressure chamber, a striker freely mounted in it, and in one of these elements holes dp of pressure relief are made of a chamber 0 ry for a given movement of the striker, a table for securing the test object, provided with an anvil, which collides with the striker, and means for holding the striker in the initial position, o t - - characterized by the fact that, in order to simplify the design and increase the reliability of operation, pressure relief ports are provided in the chamber. 2. The stand according to claim 1, which is designed so that the table for fixing the tested product is made in a vice beam, the ends of which are installed in mobile supports. Sources of information taken into account in the examination 1. USSR author's certificate number 517824, cl. G O1 M 7 / OO, 1974. 2. USSR author's certificate number 539244, cl. G O1 M 7 / OO, 1975 (prototype). tptft f