Ultrasonic transducer is an energy conversion device that converts alternating electrical signals into acoustic signals or acoustic signals into electrical signals within the ultrasonic frequency range. It is a key device in ultrasonic equipment, so no matter whether it is in the transduction mechanism or the process Design and other parties have received long-term attention.

 

Performance parameters of ultrasonic transducers

Ultrasonic transducer is an energy conversion device, and its performance description and evaluation requires many parameters. The characteristic parameters of ultrasonic transducer include resonance frequency, frequency bandwidth, electromechanical coupling coefficient, electroacoustic efficiency, mechanical quality factor, impedance characteristics, frequency Characteristics, directivity, transmitting and receiving sensitivity, etc. The performance parameters of transducers for different purposes are different, for example, for transmitting ultrasonic transducers, the transducers are required to have large output power and high energy conversion efficiency ; For receiving ultrasonic transducers, a wide frequency band and high sensitivity and resolution are required. Therefore, in the specific design process of the transducer, the relevant parameters of the transducer must be carried out according to the specific application Reasonable design.

 

Analysis method of ultrasonic transducer

Ultrasonic transducers include circuit system, mechanical vibration system and acoustic system, and the three are organically combined into a unified whole when the transducer is working. This determines the research method for it is the fusion of electronics The research methods of science, mechanics, acoustics, etc., and through the electro-mechanical-acoustic analogy, enable the three to use a unified equivalent electromechanical diagram and equivalent equations to easily conduct in-depth research.

 

The ultrasonic generator converts the 220V mains power into high-frequency current, and the ultrasonic transducer converts the high-frequency current into mechanical vibration, then amplifies (reduces) the amplitude through the ultrasonic horn, and finally transmits it to the tool head for work. Ultrasonic transducers generally have two forms: magnetostrictive and piezoelectric ceramics.

Transducer composition

Central piezoelectric ceramic element

Front and rear metal covers

Prestressed screw

Electrode pad

Insulation tube

This kind of sandwich transducer generates stable ultrasonic waves when the load changes, which is the most basic and main method to obtain the power ultrasonic drive source. According to different designs, the forms of ultrasonic transducers are mainly:

Column type (NTK type)

Inverted trumpet type (Benengxin type)

Steel back cover

Aluminum clip type

Ultrasonic transducers are mainly suitable for ultrasonic welding, ultrasonic cutting, ultrasonic liquid treatment, ultrasonic atomization spraying and ultrasonic metal melt treatment.