The Secrets To piezo ceramic sphere

The main PZT materials are used in ultrasonic motors included piezo ceramic materials and friction materials. The ceramic material is the ultrasonic vibration generating device and the sensing feedback device of the piezoelectric motor, and the friction material is the transmission medium of the output torque of the piezoelectric motor, and both performances are directly related to the output characteristics of the motor. The higher friction factor of the friction material, the smaller is the loss of the speed change of the ultrasonic motor, and the hardness of the friction material will affect the speed and propulsive force of the motor. 

Piezoelectric ceramics as the transducer material of ultrasonic motors require high curie point in the performance, wide operating temperature range,it is stable piezoelectric performance, good anti-aging performance, high mechanical strength, high electromechanical coupling coefficient, mechanical quality factor and pressure Electrical constant, low dielectric loss, wide response frequency. The ultimate determinant of the final performance of piezo ceramic hemisphere is the nature of the piezoelectric ceramic raw material. The material purity, fineness, particle size and distribution, reactivity, crystal form, availability, and cost must be comprehensive consideration and control. Currently, high power piezoelectric ceramics are used at home and abroad. There are PZT4, PZT8, and PZT5. In order to achieve better overall performance and designability, various countries are vigorously developing piezoelectric composites and piezoelectric films in order to protect the ecological environment. Research on lead-free piezoelectric ceramics and nano-piezoelectric ceramics.

Because the mathematical model of the ultrasonic motor is difficult to establish low cost piezoceramic sphere and has strong non-linearity and time-variation, high-accuracy speed and position control are very difficult. At this stage, the task of control system research is to adopt adaptive control, fuzzy control, and neural network control strategies to solve the problem of serious non-linearity of speed characteristics, time-varying, severe dependence, and uneven contact between the rotor and stator. Rotor speed fluctuations and other issues, PZT material piezoelectric sphere is so as to achieve accurate speed control and position control.

Ultrasonic motor has many advantages compared with traditional electromagnetic motor, which can overcome the limitation of the working principle and structure of electromagnetic motor and meet the special requirements brought about by the development of science and technology. After more than 30 years of research and exploration, it has been widely used in many fields such as optoelectronics, aerospace, machinery manufacturing, robotics, instrumentation, and household appliances. piezo sphere transducers are still in the initial stages of development. There are still many problems to be solved, such as the precise theory of the working process, the evaluation of technical characteristics, the analysis of control characteristics, the improvement of efficiency, the application of new vibration modes, and the development of friction materials. In order to catch up with the international advanced level as soon as possible, in addition to piezoelectric transducer sphere is increasing research efforts on the motor mechanism, structural design, and control philosophy, we must also increase the manufacturing process and detection methods of the motor.