SU576519A1 - Force measuring sensor - Google Patents

Description

one

The invention relates to a measurement technique and is intended for measuring forces inside models or products made from elastic-elastic materials.

The known sensor for measuring forces, comprising a housing in which a piezoelectric element is located, does not provide the required accuracy 1.

The closest to the technical essence of the present invention is a sensor for measuring forces, comprising two supporting ichites and a piezoelectric transducer arranged between them, consisting of two piezoelectric plasts placed in a shielding case 2.

However, the known sensor does not provide sufficient measurement accuracy.

In order to increase the accuracy of measuring the forces, two annular nyesoplates, concentric with a piezoelectric transducer and attached by external plates to support plates, and a generator of unipolar electric impulses, one output of which is connected to the internal faces of annular piezoplates, and the second output through shielding, are introduced into the sensor. the casing is connected to the outer plates of all piezoplates, shorted to the base plates.

The drawing shows an oppressible small-sized sensor for measuring forces, consisting of the upper 1 and lower 2 supporting juiiiT, to which, with the same name, are glued to the piezo-plate 3 and 4, which form the piezo former. From the inner plates of these nezoplastins lapped to each other, using a shielded cable 5, the signal supplied is fed to

measuring device (not shown).

The outer plates of the pezonas 3 and 4 are electrically connected to the base plates. Coicenter the piezoelectric transducer in the sensor are annular piezoplates 6 and 7, forming a device for periodic unloading. These plates are also glued by external plates with hardening glue to the corresponding base plates and electrically connected to them.

The inner plates of piezoplates 6 and 7 are electrically connected with each other and, during the final assembly of the sensor, are glued with viscous substance 8. In the process of this gluing, the excess viscous substance flows out until piezoplates 3 and 4 fit snugly against each other.

To connect with the crankshaft (Psalongia 6 and 7), wire 9 coming from the generator of unipolar electric impulses is connected. The second wire from this generator, as well as cable 5, is connected through the shield shielding from cover to the external plates of all piezoplates.

When acting on the force sensor P, it is distributed between the plates of the piezoelectric transducer and the periodic discharge device. Since substance 8 is viscous, most of this force is perceived by a piezoelectric transducer. The charge generated on the plates of the piezoelectric transducer from the action of the force P drains quickly, and the pointer of the recording device stands on the pool. When the unloading device of unipolar electric pulses is applied to the plates 6, they are deformed synchronously with these pulses due to the inverse negative effect. Consequently, the component of the force P perceived by the piezoelectric transducer varies according to its analogue law. With an increase in the amplitude of unipolar pulses, a moment comes when the piezotransducer is completely unloaded, and hence the signal taken from the piezotransducer increases as the amplitude of unipolar pulses increases to a certain value determined by the effective force.

This signal is measured at a deliberately high voltage of single-pole pulses or

The amplitude of the unipolar pulses, at which the signal taken from the piezotransducer does not grow, can be unambiguously judged on the force acting on the sensor.

Claims (2)

1.D. I. Ageikin et al. Sensors of control and regulation, “Mechanical Engineering, Moscow, 1965, p. 215. 2. Authors certificate of the USSR № 143585, cl. G OIL 1/18, 19GO. /about