SU635537A1 - Piezoelectric motor - Google Patents

Description

 Of the brentenle, it refers to piezoelectric motors and can be used in automation circuits as the engine of actuating mechanisms, as well as IB general-purpose household appliances.

Piezo piezoelectric engines of various designs, in which an electrical signal applied to the stator piezoelectric element, excites mechanical oscillations in it, which are transmitted to the latter through the mechanism of the piezoelectric tact with the rotor 1.

The contact system of the piezoelectric element to the rotor, made in well-known engines, causes sliding of the mechanical contact across the rotor surface at the time of the displacement of the end of the piezoelectric element with significant clamping force P1, which is accompanied by losses on the drive line and results in reduced engine life and engine efficiency. ,;

A piezoelectric motor is known, comprising a rotor and a stator in the HVA. A piezoelectric plate connected to the source was fed and secured by one m. of its iKOHUOM to the rotor by means of a spring. 2.

The objectives of the invention are to increase, H | Ie, the lifespan, the working moment and the increase in engine efficiency.

The goals are achieved by the fact that

spring is connected to the plate end through a mechanical resonator, for example, a hollow cylinder tuned to an overtone of the frequency of the power supply, the angle between the axis of the resonator and the piezoelectric plastic plane greater than 90 degrees.

FIG. 1 shows schematically the proposed engine; in fig. 2 - vector d .; The grammar that explains his work.

The piezoelectric motor consists of 13 stator / and rotor 2, to which the piezoelectric element 3 of the stator, pr) 1, is pressed by the spring 4 through a tuned auxiliary acoustic resonator 5

5 in the form of a cylinder with a resonance on one of the Oberthans of the frequency of the source and itash1. One w.M end of the piezoelectric element 3 is fixed in the stator 1 through an elastic, for example. Of rubber. gasket 6, while others rest

0 through tip 7. on the rotor. The voltage is P11tan; 1 is applied to the electrodes 8 and 9 of the piezoelectric element.

. In order to clarify the operation of the device, let us consider the forces that appear during the operation of a piezoelectric engine. By the end5. n.} 1ku through the resonator 5 (. not shown in fig. 2) right there is a constant constant force on the spring OS 4, which caused the reaction of the support of the piezoelectric element OL and their resultant F,

0 lying within the friction angle ptr, equal by definition | i, p arctg / Page (К-г - coefficient of trenn between. However: not true, 7 and. The surface of the rotor 2). The absence of a resonator on the rotor is caused by the rotational force FZ and the anti-acting force of friction F. In the proposed co-operation, the operating force F is rotated, and the resistance is exercised by the friction force F.

Lozoelectric engine works as follows.

Under the influence of the posterior ir squeezing force of the OS, a reaction occurs in the support of the piezoelectric element OL, which causes the pressing force FI to be dormal to the rotor surface. The force F is collapsed vectorially with the splash f, which arises when the electrical supply is connected to piezoelectric element 3 and therefore directed along its plane. In the known engine, i.e., in the absence of a resonator 5, the end of this resultant force 1 moves with a change in variable force F in direct DE, creating the maximum rotational force FZ at the point, and in the next half-period - braking by force of friction RP at point D. Swing end The resultant force DE is chosen so that at the time of the useful work, the end of the resultant force is within the friction angle ptr (point E), and the tip 7 moves along with the surface of the rotor 2, its sense. In the next half-period, when the end of the resultant force is outside the friction angle (b), the tip 7 slides 1PO across, the top: of the rotor and due to the friction inhibits its friction force FZ. In a piezo-electric motor pr: IZH: the pressing spring 4 acts on tip 7 at an obtuse angle to the PLANE

of the piezoelectric element 3, therefore, the part of the developed and nozoElement FS force (f 6 a) is used — on the buildup of the resonator 5, which has HIGH Q-factor and rotor band, so that its acoustic impedance with cTOpOiHbi on the slash 7 at the excitation frequency was max much As a result, the torsional line of movement of the ring of the resulting force is increased to the position of the ML, almost pericidal of the action line of the spring 4 OS (when the quality factor of the resonator is equal to infinity, MN is perpendicular to the OS). As can be seen from FIG. 2, change the slope; the movement of the coida of the resultant force. in the proposed motor driver allows an increase in its reach .. and to such an extent described by the MN line, a position that the opposing force of friction (ail fs)

can be neglected, and at the same time (the time increases the rotational force (force F). Thus, pr, IMgenenle resonator 5. “astroe, for one IPR of overtones of the frequency of the source intanp, and the corresponding oscillator m of the resonator adjoining to 1CONI.I. 7, allows to increase the torque both by increasing the rotational force F, and by reducing the friction force / -e, as well as reducing friction losses, increase the efficiency and motor life of the piezoelectric engine.

The piezoelectric element 3 of the motor is made in the form of a rectangular plate, for example, from the titanate-zirconate-lead ceramics PKD-124. Metal electrodes are deposited on the main surfaces of the plate, for example. Vzhitan: the letter of metallizing paste and then icolize in a field of 30 kVgsm at a temperature of 110 C. Permanently resistant tip 7, wahrmer, from alundum 22ХС. glued, for example, with eioxide resin. The rotor is made of high carbon steel or cermet silve, for example BK8.

Experience shows that the proposed piezoelectric engine has more than twice the increased torque on the rotor shaft at the same and April power supply efficiency of the engine up to 60%, which is one and a half times higher than the known device. Motorcycle dvitatel increases 3 times.

Claims (1)

1. Copyright Certificate. Y 217509, cl. H 02 NM1 / 00, 1965. i2. Gulta L. G., Orez A. A. The Piezoelectric Motor with Exciting Resonance, Vestny KPI, X 14. 1977.