Different sizes of piezoelectric ceramics used for ultrasonic motors(一)

The complex stator of the piezoelectric sound componentsfor ultrasonic motor is the vibration element of the motor. By testing the admittance characteristics of the stator, not only the performance index of the piezoelectric vibrator can be directly reflected, but also the performance of the ultrasonic motor can be further predicted and the equivalent circuit of the PZT material piezoceramic ringscan be obtained. The other parameters of the component are estimated. Ultrasonic motor production process requires high precision, so the production process requirements are very strict, even if the same size of the motor will be due to differences in the production of the motor's individual performance more or less biased, so when assembling the motor, you should pay attention to the following issues .

1. piezoelectric ceramics

Piezoelectric ceramic electrode zoning accuracy requirements are very strict, because the inconsistent characteristics of piezo ceramic ring sensorswill affect the smooth running of the motor, the uniformity of each zone will affect the uniformity of the motor amplitude, the error is between 2-3%.

2.the stator

The stator is a key part of the motor, so the machining accuracy of the stator is demanding. In order to prevent the piezoelectric vibration transducer from breaking due to high-frequency vibration during operation, the flatness of the bonding surface of the cheap piezoceramic rings is required to be high; at the same time, the flatness of the transmission surface of the stator must be ensured so that the rotor contacts with each other. Good, and thus ensure the output power of the ultrasonic motor; the height of each high frequency piezoceramic ringsshould be consistent to avoid the modal frequencies of the stator two phases being unequal.

3. bonding

The good adhesion between the stator and the piezoelectric ceramic is directly related to the output performance of the motor. The thickness of the adhesive layer should ensure that the energy can be better transferred from the piezoelectric ceramic material to the stator, and the dissipation of the heat of the 22Khz piezoceramic rings transducer can be improved, and the output performance of the motor can be improved; if air bubbles are trapped inside the adhesive layer, it is easy at high frequency. The degumming phenomenon occurs under vibration and the motor is scrapped.

4.the application of pre-pressure

The proper pre-pressure can make the ultrasonic motor play the best performance and prevent the serious problems of serious heat generation, large input current and large noise. Taking the TRUM60 type traveling wave ultrasonic motor as the research object, the influence of different performance piezo disc crystal (P-41, PMnS.PZN-IX) on the machine characteristics was analyzed. The motor with P-41 ceramic was used as the TRUM 60 I type. , using PMnS. PZN. The PZT ceramic motor is the TRUM.60 II.