SU832414A1 - Impact-testing machine - Google Patents

Description

(54) COVER FOR IMPACT TESTS

one

The invention relates to testing equipment, in particular to devices for testing products for shock loads.

A shock test hammer is known, comprising a housing, a rotor having sockets on its periphery for accommodating the strikers in the form of balls, a striker holder made in the form of a rigid yoke covering the rotor together with the strikers inserted into the sockets and mounted on the same axis with the rotor free rotation, associated with the body trunks, the axes of which are located tangentially to the trajectory of the boys.

After the acceleration of the rotor, a braking device attached to the housing is engaged, which interacts with the holder. The holder is braked and lags behind the rotor, and the strikers by inertia exit the rotor sockets and fall onto the walls of the housing. When reaching the end of the hull wall, the head is released and flies tangentially to the trajectory of motion, hits the barrel, and strikes the test object 1.

The disadvantage of this copra is that, due to the spread of the deceleration parameters (friction coefficient, pressing force, etc.), from the test to the test the flight speed of the heads is somewhat different from each other, which reduces the reproduction accuracy of a given load.

The closest to the invention to the technical essence is a bumper for shock tests, containing a rotor, strikers mounted on the rotor, swivel holders of the strikers, levers mounted on the rotor can be rotated around an axis parallel to the axis of the rotor, and having

the end of the rollers, the synchronizer, including a hollow cylinder with a screw groove on the inside; a surface for inserting lever rollers therein and an actuator for moving the cylinder along the rotor axis. Each of the holders is rigidly connected to the lever. The synchronizer cylinder is set in advance in a position that allows the rollers to exit the groove at a predetermined rotor position relative to the copra body. Therefore, the separation of the strikers from the holders occurs at strictly specified points of their trajectory 2.

Claims (2)

A disadvantage of the known copra is a reduction in the durability of the latch of the initial position of the holder when operating at high operating speeds. This is due to the fact that during the acceleration of the rotor, the holders with the strikers are in the initial position due to the locking levers, the rollers of which interact with the synchronizer cylinder, preventing rotation of the holders with the strikers around the axes from centrifugal forces. Thus, from the moment of the centrifugal forces of inertia of the striker, holder, lever relative to the axis of rotation of the holder, significant specific pressures P arise on the rollers of the latches rotating with a high speed V, which leads to a large value of P V and to an emergency wear of the rollers of the latches. The purpose of the invention is to increase the durability of the copra. This goal is achieved by the fact that the levers are made by two shoulders and are installed with the possibility of their second ends acting on the holders of the strikers. FIG. 1 schematically shows the proposed Koper, when accelerating the strikers; in fig. 2 - the same, when releasing the strikers from holders; in fig. 3 shows section A-A in FIG. 1. The pile driver includes a housing 1, trunks 2 connected to the housing 1, the axes of which are located tangentially to the path of the strikers 3 in the form of balls, a node; mounting test objects 4, mounted on the cut of the trunks 2. In case 1, a rotor 5 is placed, having slots 6 on the periphery for accommodating the strikers 3; a swivel holder 7 of the dies, made in the form of a rigid yoke, covering the rotor 5 together with the dies 3 inserted into the sockets 6, and mounted on the same axis with the rotor shaft 5 with the possibility of rotation. On the rotor 5 diametrically opposite to each other, two levers are installed with the possibility of rotation around the axes 8 parallel to the axis of the rotor 5. The levers 9 are double-arm, with one arm of the pins 9 interacting with the holder 7 of the strikers, and the other is equipped with a roller 10 interacting with a synchronizer in the form of a hollow cylinder 11 with a screw groove 12 on the inner surface. The copra also includes an actuator 13 for moving the cylinder 11 progressively along the axis of the rotor 5. The driver operates as follows. In the process of accelerating the rotor 5, the heads 3 are located in slots 6 of the rotor 5 and are held in this position, covering the rotor 5 together with the heads 3 inserted into it by the heads. At the same time, the centrifugal forces acting on the levers 9 tend to turn them around the axes 8 and introduce the second arms of the levers 9 into interaction with the holder 7. But the rollers 10 of the levers 9, rolling on the inner surface of the cylinder 11, prevent the levers 9 from turning. in this position, the rotor 5 reaches a given speed. When the specified rotational speed is reached, the drive 13 is activated, which moves the synchronizer cylinder 11. At the same time, the rollers 10 fall into the screw grooves 12 of the cylinder 11 and, continuing to rotate with the rotor 5, cause translational movement of the cylinder 11. At the moment of complete lifting of the cylinder 11, the rollers 10 exit from the grooves 12 and the levers 9 are able to rotate relative to the rotor 5 axes 8. Under the action of centrifugal forces, the levers 9 rotate to interact with the holder 7. By the action of the levers 9, the holder 7 rotates around the axis of the rotor shaft 5, thus freeing the strikers 3 from the holder 7. The strikers exit the slots 6 of the rotor 5 and fall onto the station The housing 1, where it moves like balls in a bearing separator, is located between the rotor socket 5 and the housing wall 1. When the end of the housing walls 1 is reached, the strikers 3 are released and fly tangentially to the trajectory of movement along the shaft axis 2 and strike test objects. The synchronizer cylinder 11 is set in advance to allow the rollers 10 to exit from the groove 12 at a predetermined position of the rotor 5 relative to the copra body 1. Therefore, the strikers 3 exit to the wall of the body 1 at strictly specified points of their trajectory. Thus, in the proposed hopper, the roller experiences only the mass of the lever from centrifugal inertia forces, while in a known load on the roller is created from the weight of the lever, striker and holder, which reduces the specific pressure on the roller, which leads to an increase in the durability of the roller. Claims Koper for bump test, containing a rotor, strikers mounted on a rotor. swivel holders of the strikers, levers mounted on the rotor can be rotated around an axis parallel to the axis of the rotor and having rollers at the end, a synchronizer including a hollow cylinder with a screw groove on the inner surface for inserting the lever rollers into it and the drive for translational movement of the cylinder along the axis a rotor, characterized in that, in order to increase the durability of the copra, the levers are double-shouldered and installed with the possibility of their second ends influencing the holders of the strikers. Sources of information taken into account in the examination 1. USSR author's certificate 670837, cl. G 01 M 7/00, 1975. 2. USSR author's certificate No. 636506, cl. G 01 M 7/00, 1975 (prototype). : %%% 1 %%%% u J