SU122325A1 - Relaxation Examination Device - Google Patents

Description

The subject of the invention is a device for investigating relaxation in samples, provided with a screw or other loading arrangement. A distinctive feature of this kind of device proposed according to the invention is the use of a spring torsional dynamometer. The latter is mounted on a split axle, driven in rotation by an electric motor through a reducer and locked in a thrust ball bearing, perceiving its load on the sample. Such an embodiment of the device provides the possibility of determining relaxation without the need to relieve the load.

FIG. 1 shows the mechanical model of the device; in fig. 2 - its basic scheme.

Sample A (Fig. 1) can be loaded with force P so that the deformation would be constant.

This condition will be met if / const. Since the sample lies on roller bearings, applying force N, it is possible to move it along planes of the bearing. The greater the stresses in the sample, the greater the force L will be required to overcome the forces of friction.

During relaxation, the stresses decrease, thereby reducing the magnitude of the force N. Thus, by measuring the drop in force, one can also find the relaxation of stresses in the sample.

The device contains a rigid frame / (Fig. 2), in the upper part of which a handle 2 is installed to tension the sample 5. When the sample is tensioned, the thrust ball bearings 4 are pressed against the frame of the L Rotating machine with the middle part of the bearings 4, as well as arrow 5 the end of the spring 6 is fixed on the upper half of the 7 split axle. On the bottom half 8 of this axis, a worm gear 9 and a JO disk with a scale, as well as the other end of the spring 6 are rigidly fixed. When the electric motor No. 122325-2 starts up -

gatel // worm to 12 causes the gear 9 and the lower half of the split axis to rotate. This half pulls the spring 6 and through it rotates the upper half of this axis. In this case, the more the sample 3 is more tensioned, the more friction is produced in the support support 4.

Thus, to rotate the middle part of the ball bearings, a greater torque is required, which, through the spring 6, deflects the indicator arrow 5.

The deformation of the specimen is maintained strictly constant (with the exception of slight deformations of the rigid frame as compared with the deformations of the specimen). During relaxation, the stresses in the sample fall, and this, in turn, reduces the pressure on the ball bearings, and a lower torque is required to rotate the middle portion of the latter. The arrow on the scale shows a drop in torque, from which it is easy to determine the drop in stresses in the sample during relaxation.

By means of a dynamometer, the device can be tared so that the arrow on the scale shows not the torque, but the corresponding force, which is transmitted to the sample.

In this way, it is possible to count a consistent drop in stresses under constant deformation, without unloading the specimen.

Subject invention

A device for studying relaxation in samples, equipped with a screw or other load device, characterized in that, in order to determine relaxation without removing the load, it uses a spring torsional dynamometer mounted on a detachable axis, which is rotated through a reducer from an electric motor and fixed in a holder of a resistant ball holder that senses the load on the sample.