Quality analysis of transducers

Ultrasonic cleaning equipment varies greatly in composition and structure depending on the requirements of the cleaning object and production scale. It can be complex, bulky equipment, or very simple structure. This article focuses on exploring the quality issues of the core components of ultrasonic cleaning equipment composed of ultrasonic power supply, ultrasonic transducer, and cleaning tank.
1. Distribution and Bonding of Ultrasonic Transducers in Cleaning Tanks
At present, some ultrasonic cleaning machine products have transducers that are too densely distributed on the bottom or wall of the cleaning tank, arranged one by one. One method to determine the bonding quality is to measure the temperature rise of the ultrasonic transducers after the cleaning tank is filled with water and turned on for a period of time. If the temperature rise of a certain transducer is particularly fast among numerous transducers, it indicates that the transducer may not bond well. This is because the sound radiation is not good at this time, and most of the electrical energy is consumed by the transducer and generates heat. Another method is to measure the impedance of the transducers one by one under small signal conditions to determine the bonding quality.
The bonding quality between the ultrasonic transducer and the cleaning tank has a significant impact on the overall quality of the ultrasonic cleaning machine. It is not only necessary to adhere firmly, but also to ensure that the adhesive layer is uniform, without missing glue, and no cracks are allowed, so as to maximize the transmission of ultrasonic energy into the cleaning fluid and improve the overall efficiency and cleaning effect. At present, some cleaning equipment is designed to prevent the transducer from falling off the cleaning tank. Adopting a screw and adhesive fixation method, although the transducer will not fall off, there are many hidden dangers in this connection method. If the welding quality of the screw is poor, such as not perpendicular to the surface of the stainless steel plate, the adhesive layer is uneven, even with cracks or missing adhesive, and energy transmission will be weakened; On the other hand, poor welding can also affect the smoothness of the stainless steel surface, leading to accelerated cavitation corrosion and shortened service life
2. Selection of ultrasonic transducer structure
When the electrical power of the input ultrasonic transducer is the same, due to the larger radiation surface area of the horn compared to the rod transducer, the sound intensity of the radiation surface is lower, and the cavitation corrosion on the surface of the stainless steel plate bonded to it is smaller. The service life of the cleaning tank (or immersion transducer) is extended. Therefore, in general, it is better to use a horn shaped transducer. In order to further improve the sound radiation efficiency and broaden the frequency band, China has developed a semi perforated structure broadband ultrasonic cleaning transducer. This type of ultrasonic transducer has more prominent advantages, especially in the higher frequency range (above 40KHz), because it can weaken the adverse effects caused by lateral vibration. Due to the wider frequency band, it is also conducive to sweeping cleaning