SU505912A1 - Device for measuring model loads - Google Patents

Description

one

Devices for measuring loads on a model are known, including an example of an aerohydrodynamic experiment that contains a holder of a test model, a fixed support, a dynamometer with elastic sensing elements and strain gages included in measuring circuits. One of the sensing elements is made in the form of a continuous elastic diaphragm with strain gauges mounted on it to measure axial force and attached to it through the outer rim of another gauge in the form of a cross with thin-walled radial spokes on which strain gauges are attached to measure torque.

The purpose of the invention is to measure axial force, torsional and lateral moments.

In the proposed device, the holder of the model is rigidly attached to the diaphragm located with a gap relative to the fixed support, and the spokes of the sensing element are attached to the outer rim through elastic hinges.

The device is represented on the drawing.

The design consists of a movable support (cup) 1, a fixed support 2, a diaphragm 3, elastic beams 4, elastic hinges 5, strain gauges 6, holders 7. Elastic beams 4 are condo rigidly connected with one 2

Butt support 2, the other end through elastic hinge 5 - with support 1. At the same time, the plane of the smallest rigidity of the hinge is aligned with the inner surface of the support

1. A diaphragm 3 is rigidly connected to this support. A gap a is formed between the inner surfaces of the diaphragm and support 2 with elastic beams fixed on it 4. To the outer surface of the diaphragm attached

the holder 7 is connected to the model under study B. On the elastic beams 4 and the diaphragm 3, strain gages 6 are strengthened. A common variant is also possible when the earth is the holder 7 and the model under study is attached to support 2.

Aerodynamic loads acting on the model under study deform diaphragm 3 in axial and transverse directions. The magnitude of the signal arising in the strain gages 6 fixed on the diaphragm is proportional to the measured axial force and pogregerennye moments M and M ,,. In the action of torque, the diaphragm has the greatest rigidity and is practically insensitive to the action of torque. It transmits the torque through the movable support 2 to the elastic beams 4. The signal arising in the resistance strain gages 6 fixed on the beams is proportional to the measured

torque value. The action of axial force and lateral moments of the beam is practically insensitive.

Thus, the voltages in the device are separated:

the diaphragm is sensitive to the action of axial force and lateral moments and is insensitive to the action of torque; Elastic beams are sensitive to the effect of torque and are insensitive to the action of axial force and transverse moments.

For measuring loads, a Wheatstone bridge is used, as is usually the case with electrical strain measurement.

Load measurement results can be recorded by automatic AR-TsAGI recorders, integrating voltmeters or an oscilloscope.

Subject invention

A device for measuring loads on a model, for example, when aero-hydrodynamic

the experiment containing a holder for mounting the model under study, a fixed support, a dynamometer with elastic sensing elements and strain gages included in measuring circuits, one of the sensing elements made as a continuous elastic diaphragm with heat resistors fixed on it for measuring axial force and attached to it through an external the rim of another sensitive element in the form of a cross with thin-walled radial spokes, on which strain gauges are mounted to measure the torsional torque, characterized in that, in order to measure axial force, torsional and transverse moments, the model attachment holder is rigidly attached to the diaphragm located with a gap relative to the fixed support, and the spokes of the sensing element are attached to the outer rim through elastic hinges.

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